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This is the same story as spam (though we'd be happy eliminating spam); it started out as a novelty ("look what I can do!") and slowly migrated into an extremely profitable (and largely criminal) business. The fact that it's so poorly policed (I'm not talking filters here) makes it a perfect vehicle for all sorts of criminal ventures that vastly pre-date email, the internet, and even the fax machine (though most of these scams were seen as faxes 40+ years ago). Specifically, drug peddling, advance-fee fraud (Nigerian 419 scams), fake charities, crap merchandise, and the list goes on.

Congratulations, BitTorrent pirate networks, you are now "mature" because the criminals have you in their cross-hairs.

As to whether this is "the end of" anything ... I strongly disagree. People forget that BitTorrent is a protocol. Piracy may be one of its more visible applications, but there is so very much more. Criminal spam destroyed joke spam and most bulk email, but email has remained (well, it might eventually be obsoleted by Facebook Messages, SMS, IM, etc, but that's not really spam's fault ... and is an entirely different debate).

This is really about the use of BitTorrent to transfer copyrighted material and not about the protocol itself. Malware will persist in pirated software and media and people will get better at detecting and eliminating it. There are invite-only BitTorrent communities that closely monitor their userbase and content library for this sort of thing. These will only get more popular. There in an increased volume of free anti-virus applications out there (Avira, AVG, and Avast, ClamAV, and more), and there is also an increased variety of platforms people use (Mac OS is on the rise, as are the various smartphones, not to mention the less-notable increases in F/OSS OSs). There is also the legal fight against the MPAA/RIAA (MAFIAA) conglomerates, which seems to be heading in a good (albeit slow) direction for fair use.

We're seeing legitimate software and media increasing its adoption of free distribution; upcoming artists are embracing Creative Commons licenses, Free Software is immensely popular and will get a major bump once China, Russia, and other governments start to make good on their promises to dump Windows, and mobile phones are entering the arena.

Phones' 4G technology symbolizes the marriage of high bandwidth with high computational power, which trivializes things like streaming TV over your phone. 4G also represents an IP telephony model (VoIP), which means any cellular carrier that offers TV (currently all of the major players) must offer it as IPTV. Even my cable connection is IPTV (I can see my router's downstream byte count add up while watching TV). Couple this with Netflix and its competitors having quickly adopted their paradigms to allow streaming their content to any computer connected to your TV (video game consoles, smarter TVs and DVD/BluRay players, specialty boxes) as well as other vendors like Boxee and Hulu and you have a streaming-TV revolution.

How will this play out with respect to "piracy" remains to be seen, but I think we can see hints of its hopeful outcome in looking at the past battle of music, won by iTunes and Grooveshark; why get a questionable copy when a legitimate one is so much easier to obtain?

Avira AntiVir is quite good, in my opinion. http://www.free-av.com/

'Surely the only way to really scan a computer is by booting into a guaranteed-clean OS?'

Yes, and there are a bunch of different, generally Linux-based, bootable CDs that do exactly this. Several of the major antivirus companies make these available, and I tried about half a dozen last year. Not all of them worked well (out of date, or ran slowly, or found too many false positives and deleted them without asking!), but I was happy with the Avira Rescue System:

http://www.free-av.com/en/tools/12/avira_antivir_rescue_system.html

One nice thing about this one is that they update the image 'several times a day' so you don't have to rely on the target system being networked to do an up to date scan (though a net update option is available if you can use it). Hardware support could be more complete (I had to revert to a VGA connection on one system) but otherwise no problems. I haven't tried running this from a flash drive, but there's a guide here:

http://forum.avira.com/wbb/index.php?page=Thread&threadID=94935

Avira AntiVir - http://www.free-av.com/ --- free version. It scores high on all independent tests and isn't crazy about hogging your resources or slowing your machine to a crawl.

"used to"? It still is: http://www.free-av.com/en/products/1/avira_antivir_personal__free_antivirus.html - and the premium version, clearly labeled, "Avira AntiVir Premium", is sold in the shop I work.

Use Avira AntiVir Rescue System to get the system into a state where it can boot into Safe Mode, then finish off with MBAM and possibly SmitFraudFix.

      --- Mr. DOS

Sounds like it's time for the Avira AntiVir Rescue System.

      --- Mr. DOS

Add in an anti virus software that does the same X number of processes in the background plus Ad-Aware thats way more bogged down software than ever. Ad-Aware used to be simple, clean and sleek, now it's just bloated shovelware (how quickly did they move from Version X to SE, to Version X.1?)

Stick with Spybot, Malwarebytes, HijackThis and a decent backup like Nod32, Avast or AVG, imho.

Some good recommendations (I'd add Avira AntiVir Personal to your list), but I think Microsoft Security Essentials (released 2 weeks ago) is now worth considering for free, non-bloated virus/malware protection. The initial reviews seem pretty good.

They likely would have never understood why you need to pay a lot for top end protection, nor would they likely have payed for it.

Hell, I never understood that either. Why should anyone who just forked out $xxx for a brand-new OS then be forced to pay yearly "protection money" as well? Sounds like a racket to me.

I regularly end up helping people who've bought a new PC which comes infested with the Norton malware. If you don't rip it out before the free trial ends it is virtually impossible to get rid of it. And, of course, if you wait until the trial expires, you've probably caught some nasty - their package is, to put it bluntly, a bloated and useless piece of shit.

It sounds like Microsoft's offering is considerably less obtrusive, and end users will not be hit with the problems I've seen with my preferred solution, Avira.

I've used, and recommended Avira for years, it is completely free for non-commercial use and all you have to put up with is a once-a-day popup advert for their paid products. This is a good thing for non-technical users, it gives them a reminder that their anti-virus has just updated and is still working.

What really, really pissed me off was Vista. XP's security control centre quite happily recognised Avira, but Vista "conveniently" failed to recognise it. This means that unless you're reasonably technically savvy you will get constant nagging that you have no antivirus product. I wonder if that had anything to do with their plans to release this new product.

Seriously, I've had process explorer in my kit for a while, but haven't used it for much lately. Have you tried Malwarebytes, I wonder why it's not on your list. FWIW if you can't boot your system at all one of the guys from MBAM suggests Avira http://www.free-av.com/en/products/12/avira_antivir_rescue_system.html haven't tried that one yet, but it's on my list of potentials, so I'd love to hear if anyone has worked with it.

http://www.free-av.com/

Easy , free

Personally, I think people are aching for alternatives to the current big players like McAfee.

I'm aching for alternatives to bloatware like AVG, actually.

Avira.

This, of course, is for home and personal use.

Avira is faster and better at catching virus.

• Antivirus (use with firewall)
  • NOD32 ESET (fast, reasonably secure)
  • GData (slower, best possible protection)
  • Avira (fast, highly secure, & free version)
• Firewall (use with antivirus & antispyware)
  • Comodo (free, hard to configure)
  • PC Tools (free, easier to configure)
  • Zone Alarm (pay & free versions)
  • Agnitum Outpost (pay)
  • Jetico Firewall (pay & free versions, hard to configure)
• Internet Security Suites
  • Kaspersky
  • GData
  • BitDefender (cheapest)

That and lock down your browser, by installing Firefox, with NoScript, Better privacy, adblock plus, and deny cookies by default, then enable the cookies you want using the cookingSafe extension. Do that no matter what security software you have installed. Or of course you could save yourself a great deal of trouble by using Linux.

First: Get this. If you got a rootkit, this should find it. unless it's something zero day. If it finds stuff, then reboot back into windows and run something like Malwarebytes Anti Malware or Spybot Search and Destroy for a few days (a week or two with Spybot. They only update on Wednesdays) to get it completely cleaned out. Windows Defender also works good here and adds realtime scannning to the mix.

Second: Like someone above posted, Check for Drives Running PIO in Device Manager. If you find any, run the resetDMA Script someone above posted. ALso Check your BIOS for changed settings. Dying CMOS batteries can cause a lot of havok with DMA settings depening on the BIOS defaults.

Third: Test Hardware. Contrary to Popular belief here, Windows NT Kernel Failures, *Especially Blue Screens* Are usually caused by either a Hardware failure or a Driver failure. If it's been running great and then BAM, check hardware first. The Ultimate Boot CD has all the tests you need. Test for RAM errors and test your Hard drive using the Drive Specific diagnostic program.

Forth: if all else fails after this, backtrack. If you installed something recently, and the machine started acting weird afterwards. uninstall it and see what happens. System restore (if it actually works) also comes in handy.

Finally, a Tip. Stay The Hell away from "optimizing" software. Just about every Registry optimizer I've ever seen screws up more then it's worth. Speed boosters tend to slow things down in the long run or lock windows, and any disk optimizer basically does nothing different than defrag C:. Even Microsoft's Registry and cleaning offerings on their onecare site has screwed me over in some cases, and if they can't optimize their own OS... Just say no to them.

I have found Avira useful. Be warned that it is nagware, though. Every time you update definitions it will post a full screen splash screen.

It sounds like AntiVir is what you want. I let my nephews play their online games on a spare box and the youngest tried to download a "free" online game that was full of adware/malware crap. AntiVir stopped it cold and threw up a nice little shitfit which scared him off installing it. AntiVir also has a really nice,easy to customize interface. Like I don't download email,so I simply didn't have it install the email "shield" at first install. And of course free is always of the good.

As for the article,it simply won't work. OEMs are getting too much money for time limited crapware AV programs to install this,and MSFT can't install it in the OS because of antitrust. So I bet this will be one of those things that sits quietly on the server being forgotten. Not to mention it fails to address the problem of pirate Windows boxes. Because we all know this will only be available for "genuine" Windows,and yet the biggest source of trojan spambots out there is all the pirated Windows boxes that have never been updated thanks to fears of WGA. So while it is a nice idea in theory,I'm betting it just withers on the vine.

Why does a retarded answer like this get moderated 4, insightful rather than -1, off-topic?

I doubt she gives a shit about Ubuntu or wants to use it.

ScrewMaster was correct, a fast lame first post which don't offer any insight or a solution.

What's the purpose of having useless posts like this in the thread? It won't help her.

My suggestion is avira. It's good at its purpose and uses few resources.
I like comodo firewall to and they have an anti-virus called "anti-virus 2" I believe but it's beta and I don't know how good it actually is.
Comodo got plenty of free totally usable products.

I recommend Avira Antivir Personal. Very Lean, fast, customizable and through.

Only problems is it pops up an Ad to upgrade to the pay version every time you download an update and it can be false positive happy when turned up to it's fullest settings and definitions, but otherwise it's one of the best scanners I've seen.

In case you wanted an ACTUAL answer,and not just a bunch of geeks shouting Linux I would suggest either Comodo if you would like one with a built in firewall,or AntiVir if you just need AV. As a Windows repairman I have used both on many customers machines and they work quite well.

I know that shouting "Linux" is a great way to Karma whore here,but the simple fact is I'm sure he asked about Windows Av for a reason. Sometimes Linux simply isn't the right tool for the job,as anyone who has tried to get those damned Lexmark all in ones to work or run into one of the bazillion SMBs that have custom VB apps that are mission critical can tell you.

I use Avira AV on the WinDOZE systems at my house.

It's free for personal use, and companies have to get a site license...

For years I've been recommending Avira to friends, family, and customers. I know when I used it, it was a top notch free anti-virus product, however, I haven't used it in years (been using Linux exclusively now). Can anybody confirm it's still light and effective or has it turned in that time?

I recently gave up on AVG. It was a nice free option until this version 8. Surely, Grisoft knew this was a big problem for a long time. They're not the only people who thought this approach of extra verification would be a good idea. MCAfee did it, Opera (I think) just linked up with one of the Microsoft spawns that tests everything and drags web use to a crawl. It's as poor an idea as "background" disk defragging which does nothing other than work the drives because it's not possible to sort a drive which is in flux.

Avast! is frequently recommended as a free anti-virus. BUT...do some research and you'll see it's not that great at catching known junk. ESET does test very well but you only get 30 days of free use. Avir's free version does seem to offer full integration (in-line scanning, auto updates, etc.) which I don't remember being there a few years ago when freeware scanners only worked on-demand. http://www.free-av.com/ It tests very well, actually, better than AVG and Avast!

In their defense, if I remember correctly, AVG DID offer free fully integrated inline scanning first with a decent catch rate. Why did it take them so long to comprehend version 8 was a hog and would generate so much anger and resentment? Who knows. Maybe their time has past just line PKZip...

Try Antivir!

From my personal experiance, as a computer service technician, it finds AND fixes infections where Norton (Personal + Corporate) and AVG find nothing.

http://www.free-av.com/

I guess you've never used Avira then?

free-av.com

Free antivirus for Windows, Linux, BSD, and others.

Since most of the posts are not answering your question at all, here are some programs which can help.

I have been fixing Windows computers for over 10 years and can suggest the following programs from personal experience. There is no guarantee that they will find all keyloggers but they will detect the progs you find by using google.

1) Spybot Search & Destroy (free) http://www.safer-networking.org/
    This is a spyware checker, cleaner. It will also find keyloggers and screen capturing software
2) Antivir (free for personal use) http://www.free-av.com/
    This is an Antivirus / malware program which I have found to kick the shit out of Norton Antivirus (Personal + Corporate) and McAfee.
3) Norton Antivirus 2008 (not free)
    This is another antivirus program, it is not as good as Antivir but it may contain different malware signatures then Antivir.
4) Adaware (free) http://www.lavasoftusa.com/
    Like Spybot but less strict, I don't use it anymore but you should run it anyway.
5) Windows Defender (free) http://www.microsoft.com/athome/security/spyware/software/default.mspx
    This one is made (purchased) by Microsoft and is actually quite good, I can highly recommend it to remove crap from a computer. This one is free and includes an "active shield"

If you run suggestions 1,2,4 and 5 above you can assume that your computer is clean. To be sure format and reload.

As for the rest, follow the advice above and end the relationship....

• "System drive C:\ with label "___" uses NTFS file system and Rescue Disk may not have access to this drive. Would you like to continue creating Rescue Disk anyway? (Y/N)"

I'm a bit surprised that, out of the "Three A's" of free Windows antivirus (AVG, avast!, and AntiVir), only AntiVir seems to provide a free bootable CD/DVD antivirus tool (and it's seperate from the installed Windows tool).

• "System drive C:\ with label "___" uses NTFS file system and Rescue Disk may not have access to this drive. Would you like to continue creating Rescue Disk anyway? (Y/N)"

I'm a bit surprised that, out of the "Three A's" of free Windows antivirus (AVG, avast!, and AntiVir), only AntiVir seems to provide a free bootable CD/DVD antivirus tool (and it's seperate from the installed Windows tool).

Ah. Lazy me for not searching more closely before asking... just found this as one alternative: http://www.free-av.com/en/tools/12/avira_antivir_rescue_system.html.

AV Comparatives does not give AVG very good marks, and my experience has reinforced this. NOD32 and AntiVir are the best out there by their results. AntiVir is free for personal use and they both perform on par with Norton without bringing systems to a crawl.

Oddly, I haven't seen many truly serious rootkits. Most of them have been on pre-SP2 XP machines, which are (thankfully) becoming rarer.

Avira Anti-Vir Free Edition is also awexome. Free for personal use. http://www.free-av.com/

• Openoffice.org (use word processor, spreadsheet, presentation, database, and similar applications)
• Picasa (view/edit photos)

Internet Tools

• FireFox (browse Web sites)
• Gaim (chat with users of AIM, YIM, MSN, IRC, etc.)
• Thunderbird (e-mail)
• Pegasus Mail (e-mail)
• Macromedia Flash Player (watch Flash animations within Web browser)
• Java Plugin (run Java applications inside Web browser)

Basic Tools

• 7Zip (compress/decompress files)
• EditPad Lite (edit text files)
• vim/gvim (edit text files--advanced)
• Adobe Acrobat Reader (view PDF files)
• PDF Creator (create PDF files)

Security Tools

• ZoneAlarm (firewall - detect unwanted Internet access)
• Avira Antivirus (detect/remove viruses)
• ADAware Personal SE (detect/remove spyware)
• SpyBot Search & Destroy (detect/remove spyware)
• HiJackThis (detect/remove spyware)
• Discombobulator (make Windows more secure)
• Shoot the Messenger (make Windows more secure)
• Unplug-n-pray (make Windows more secure)
• PGP (encrypt/decrypt files or e-mail for privacy) - see admin for more details

Advanced Tools

• Virtual CD-ROM Control Panel for Windows XP (mount ISO images as filesystems) from MSDN
• IMAPSize (manage/search/backup an IMAP mailbox)

One more worth checking out is AV Personal from Avira. I've using it for years (till I switched to Linux) and always recommend it first to friends and family. I've always noted it to be lean and effective.

Free AVG updates daily.

Nobody here mentioned AntiVir. It's free (for personal use) and I've also seen it touted on slashdot in the past. I use it on all the computers in home and it's fast, not annoying* (see auto-update ad) and efficient.
Caveats:
* No email scanning in free version.
* If auto-update is turned on (as it should be!) when it starts the updating process it launches an ad pop-up touting their non-free version and products.b

What utility should I use to defrag? Not the one with Windows? I've left this running on my computer for a weekend and got back on Monday to see that it restarted itself.

Also I have heard about the problems with Norton's and I am looking into TrendMicro to replace it after my subscription is up.

Hackers are using techniques popularised by developers of open-source software like Linux to improve their malicious code, a researcher at McAfee has said.

Nowhere is this more apparent than within the growing families of 'bot' software, which allow hackers to remotely control infected computers. Unlike viruses of the past, bots tend to be written by a group of authors, who often collaborate by using the same tools and techniques as open-source developers, said Dave Marcus, security research and communications manager with McAfee's Avert Labs.

We've seen many cases where Microsoft "engineers" have failed. How many times has Bill been embarassed because of a blue screen or a failed demo? Microsoft is not the smartest bunch of people in the world. They know how to get their poorly developed products bandaged so they'll keep working.

I lost faith in Symantec when their cure for a worm was worse than the worm itself (0.dir disk filling anyone?). I recently lost faith in McAfee because their startup checking program (shstat) chokes my P4 2.4Ghz to 100% CPU usage for over two minutes at every boot.

I have been slightly impressed with Microsoft's Antispyware program because it found and removed a few things that Search and Destroy and Ad-aware missed. I will not however pay for it when it becomes part of LiveCare.

Even though I'm still using XP (I'm too lazy to use Linux and don't make enough to buy a Mac), I'm at least able to use it now thanks to the /. community pointing me to AntiVir http://www.free-av.com/

I've been working with computers and networks for 22 years. Many a time I've seen a bad infestation as described in TFA. It would take about 2 hours to clear everything, and even then something is likely broken (usually IE or control panel) so badly that it won't function 100%. It is often much, much easier and faster to backup data, reimage and restore data. Besides, most of the time what's causing the infestation is all of the stupid freeware that will be immediately downloaded once the system is up and running again.

It's like trying to teach people how idiotic using AOL is. They don't want to learn and keep their computer safe and running smoothly; they want smiley icons, stock tickers and a weather monitor. I swear if someone just came up with an appliance that did all the stupid things freeware programs do, most people (read "unwashed masses") would never need a computer.

I've recommended AntiVir to a number of family and friends. The usability increases with each iteration, and gives you options to schedule automatic updates. The only downside is during updates, it sends up a single advertisement for thier full-featured product. So far, I've installed it for my girlfriend, sister, mother, and grandmother. No one has yet had a virus breakout - of course, the promotion of Firefox to Default Browser(TM) and a little user education goes a long way.

As a sidenote, check out the Anandtech Consolidated Security Thread for great commentary on a slew of security products. As of version 6, (now version 7) AntiVir is rated at a 84.5% detection rate.

As for myself, I just use good ol' common sense and a router.

Above your comment, nobody has also mentioned AntiVir PersonalEdition Classic which I'm running (but thinking about switching to AVG). When I switched from Norton to AntiVir, I couldn't believe the difference it made...

It's hard to recommend Norton when they require manual removal of malware files that aren't in memory. C'mon Symantec, that helps nobody!

You bet it will slow down. Just compare Norton Anti Virus solution versions 2003, 2004, 2005 & 2006. It's like slow, slower, slowest, crawling... (well you get the idea).

I run Windows XP at home and no protection software is installed (resident / layers). Occasionaly I run free AV, MS antyspyware, SpyBot S&D but basically it turns out they don't find a thing.

How do I do it: using linux router and more importantly think before you click!

That's right - use your brains & you don't need any security suite.

I switched from Norton about a year ago and I have to admit I couldn't be more happier with the speed of my computer. I currently have AntiVir PersonalEdition Classic installed and I couldn't be more happy with it. All the settings are available to met, it's fast, and it tells me exactly what it's doing with it's guard feature (it shows exactly what files it's scanning as you use your computer). The only setback is that the free version doesn't automatically update for you and the scheduler is a little funny to use, but those are things I'd gladly do manually in exchange for MUCH MUCH better speeds.

I have unyielding hate for Symantec. I've spent countless hours trying to get their products to properly allow connectivity for various programs for other people, and even more hours uninstalling it after it wouldn't listen to my yelling.

Nothing Symantec has is good, or can't be replaced by a free alternative.

Anti-Virus? AntiVir (If you want to pay, they have a premium version, too)
Firewall? SP2 comes with a moderate firewall that works well. There are a good deal of free firewall programs out there, not to mention that many routers now have some sort of firewall software on them.
Ad-aware and MAS have taken care of any spyware problems I've had to deal with (except for some of the really evil ones.)

Any and everything else can be taken care of by good judgement and learning some PC common sense. Don't arbitrarily accept downloads that IE pops up with. Don't open every attachment that claims to be a dancing Ronald McDonald. Don't listen to every e-mail propogated by the feces of the internet that various programs in your windows folder are viruses.

There is absolutely no need to pay $100 for Symantec's horrible piece of crap. People would be better off without it.

The article states that the virus executes on the third of this month (tomorrow.)

Why not just wind back the clock?

I'm serious. I've fooled many a shareware program that locks the program after x days by setting the date back to when I first installed it (or even earlier, which makes for some funny notices.)

Unless the Kama Sutra virus is programmed in such a way as to store the date and time installed, and then keep track of every (milli)second that's past, and execute once enough seconds have passed to put it on the 3rd, I would think you could easily fool it by simply changing the date on your computer back a week or two. If you're really anal about calendars, you can find a year where the months start on the same day.

Yes, this would mess up some other programs that use the computer's date, but temporarily wonky programs are better than completely deleted files, no? So, set the clock back, and wait until Microsoft finally releases their patch or whatever, if you're afraid that another virus scanner hadn't caught it.

Besides Spybot and Adaware, I use the following programs:
SpywareBlaster - Prevents Spyware from being installed
Microsoft AntiSpyware - Completly free, and has nice active protection. Have a 'special' versions of Windows, use an alternate download source.

With respect to Viruses, please read the following article: Mega Antivirus Test.
Summed up: AVG sucks, Anti-Vir finds the most virus, Kaspersky 5 finds most unique stuff, and Kaspersky's online scan owns everything.

Also I'd recommend using a NAT. All of this is prevention/reactive stuff, though I think the Hijack This + Google is the best for nasty stuff, as mentioned.

If I see anything like that on a website, I pretty much instantly discount anything that website has to say. It's juvenile, and wrong,as I get pop-ups with Firefox, and plenty of viruses attempts whiz right past firefox, and don't stop until my virus checker gets 'em (http://free-av.com./

Because our DSL-Router (Windows XP pro with Kerio Winroute 5) had a serious error I was forced to go online by 56k-ISDN Dial-Up with my own Windows XP pro Computer.
My system wasn't Up-To-Date (maybe 2 or 3 weeks without Windows Update) and I had no Firewall installed. About 2 Minutes after I dialed up my Computer shut itself down (I turned on Windows XP Firewall and downloaded a Firewall I really trusted).
As you can see: The up/downstream is not very important ;)
It's more important to have a nice Firewall (I use Kerio Personal Firewall which is Free, but the AdBlocker and some other additional stuff will be disabled after 30 days of testing, but the Firewall still works and can be configured...) and good Antivirus (like AntiVir PE Classic which is free for personal use, too).
And since you're online with DSL you can turn auto-update for both programs on.
And of course Windowsupdate, if you want to (I only use Service Packs because I trust FireFox 1.5 and my sense for dangerous stuff)

OK, with Dial-Up you may be more secure because you're not always-on, but thats somewhat foolish. Because if you don't go online at all you're quite safe, too.

If you want a good antivirus, I suggest AVG or Avast. Both are excellent free products that are nowhere near as invasive as Norton.

However, I'm not sure if there are other products more suitable for corporate use. But maybe these have special "editions" for that too. I'm talking mostly about server centralized immunizing features. But I agree with Norton/Symantec having poor security products. The defaults in.. get this... Symantec's anti virus tool blocked VNC and Remote Desktop connections for me once. Found it out after turning Smoothwall inside out trying to see what the hell was the problem, but it was apparently doing what it should all along.

Btw, another good, free, non-invasive and rather resource efficient one suitable at least for home use is Antivir. For Windows 98/Me/NT/XP/2000/NT, and also Linux/FreeBSD/Solaris.

AntiVir is SWEET!
I love AntiVir, head to head with Norton it destroys it. I've never tried it against AVG though.
AntiVir is what I usually recommend to people.