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"Cobol is in attrition as far as most of the world is concerned."
Old working code has a huge advantage over a rewrite... It works.
You may be shocked how much effort people will make to keep old software running.
http://www.comwaretech.com/PDP...
http://www.dbit.com/

Yes, there are. I have one, and a Catweasel controller that can read and write basically any format on it.

The 8 inch standard format is very similar to the 1.2MB 5.25 inch format. Actually, it's the other way around, as when IBM built the PC AT and the high-density drives for it they apparently intentionally made the formats nearly identical. They're so close that computers that use 8 inch diskettes can typically be modified to run with 1.2MB HD 5.25 drives and media with only a new controller to drive cable and new drive power supply (8 inch drives typically take either AC mains power to run the spindle or 24VDC, and 5.25 drives take 12VDC to run the spindle). See http://nemesis.lonestar.org/co... for some tech info on how to do this with one of the first multiuser 'personal' computers, the Radio Shack TRS-80 Model 16 (and descendents the 16B and the 6000). Also see http://www.dbit.com/fdadap.htm... for the 'proper' adapter board.

8 inch diskettes are famously reliable with good quality media, and the bits aren't packed so densely that an EMP event will wipe them out, as long as they're in a faraday cage with sufficient attenuation and power handling capacity.

Current production high-density PC FDC's can easily handle the 8 inch drive with the proper adapter cable, but the number of supported formats is small. More flexible is the USB interfaced Kryoflux, and the PCI Catweasel MK3 and MK4 (the Kryoflux is currently in production and available for purchase; the Catweasels have been out of production for a while and are a bit difficult to obtain last I checked; I bought my MK4 from amigakit.com, but they appear to only have the Amiga-specific MK2's in stock.

I see that there are emulators around so maybe you could retain your software and retire the hardware (in the summer, anyway).

Yes; http://www.turbohercules.com/. Near and dear to my heart is the CDC Cyber series on which I had to run my COBOL assignments at uni; http://members.iinet.net.au/~tom-hunter/. Anyone also do assignments on PDP 11/70's as I did also? http://www.dbit.com/. Christ, I bet there's an emulator for any platform and architecture that's existed.

Even OpenBSD would be iffy.
VMS or Z/OS maybe, While the Unix's have gotten much better at security they where seen as being highly insecure compared to Mainframe and Super Mini OSs.
Why is windows being use?
It is cheap and really available and runs on COTS hardware.
That is the important part running on COTS. There are companies today that create PDP-11 "clones" that are really PCs running an Emulator and with some special hardware interfaces.
Why you ask? Because there are still systems out there that require a PDP-11
http://www.dbit.com/
http://www.logical-co.com/
http://www.stanq.com/charon-11.html
and http://www.migrationspecialties.com/Emulator-PDP-11.html
Imagine depending on systems like these. By going with COTS they figure that they can keep upgrading on the cheap. Plus people that "know" PCs and windows are common and realty cheap.

Of course... Here you go. And this although ethernet support under Windows requires WinPCAP, which suggests that it might have been around for some time.
With a bit of work, they could probably be compiled for Linux on something portable, or even Windows Mobile and you *could* have a PDP-11 on your phone.

So how many PDP-11's can you run on a Pentium 4 anyhow?

You could shell out some bucks for Ersatz11 and find out. It runs under Linux, and it runs fast. You can even attach Q-Bus and Unibus hardware with an adapter.

How is DNA a demonstration against macroevolution? With billions upon billions of years and billions upon billions of joules of energy flying every which way, I would be very surprised if life didn't start.

I'm going to borrow a couple of basic analogies to illustrate the point. Don't get carried away nitpicking the details of each analogy, just consider the broad view. The porpose of the analogies is not to prove or disprove evolution, but to illustrate some things about statistics.

If you sent a tornado through a junkyard, would you expect it to form a working B52?

My answer: No. I suspect your answer would be "what are you? nuts? the cases aren't comparable!" - but they are. A tornado brings with it energy, which is needed for assembling things, and the junkyard suplies raw materials, something for the energy to act on. In fact, this analogy gives you the advantage, since a tornado has a good deal more structure available than raw energy does.

If you sent a trillion tornados, one at a time, through the same junkyard, would you expect a working B52 to form as a result?

My answer: I would expect it to form a very fine metallic sand. Your answer?

OK, let's abandon illustrations connected with reality, and start giving you som serious ground. If you sent a trillion tornados through a trillion junkyards, would you expect to see a working B52 formed? Would it help to re-run the experiment a trillion times?

My answers: no, and no. Your answers?

If you sent a trillion tornados across a trillion copies of the biggest B52 junkyard in the world, would you expect to get a working B52 in the process? Or even something that flew under its own power, maybe a mutant with nineteen jet engines (three of which worked) and seven wings?

My answers: no, and no. Your answer?

Let's go back to that most popular of analogies, the infinite number of monkeys.

We don't have an infinite number of monkeys, so let's consider a very large number of them. Their task is to type out The Origin of Species, starting with the title. We'll use Golden Tamarinds, because they're small, and pack them and a little typewriter into a cage 10cm on a side. Given a surface area of 500,000,000 square kilometers, if we paved the entire Earth, oceans too, with cages, we'd fit 50,000,000,000,000,000 (5x10^15) cages on Earth. Let's stack those a kilometer high to get 5x10^19 cages. We don't know how many planets there are in the universe, but let's guess that there are 10^22, roughly one for every single star in the universe, and that they're Earth-sized. Cover those with tamarinds too. We're up to 5x10^41 tamarinds - oh, the plumbing...! Being fast little buggers, they type ten random characters a second, so we have 5x10^42 random keystrokes available every second to apply to our manuscript. That's a lot of keystrokes!

The title of Darwin's work is `On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life.' That's 21 words in 119 characters, and a boring typewriter keyboard like this one has 63 symbols available. We'll tape over keys like tab, carriage return and backspace because layout is of no interest to us. Because we don't want to spend forever dithering around about how often a tamarind will hit shifted keys, or how much favour the spacebar gets because it's bigger, or ASDFGHJKL get because they're central - and also to maintain that typing speed - we'll arrange those 63 symbols in a "mammary" style keyboard with equal-sized unshifted keys and an equal chance of each being hit.

Ready to roll... each keystroke stands a 1/63 chance of being the right one, so it will take an average of a bit over 10^214 keystrokes to complete the title. Dividing by 5x10^42 gives 2x10^171 seconds to type out the heading... but the universe is less

Dbit's PDP-11 simulator

Imagine doing table joins swapping large tables in and out of 4 megabytes of memory - or less - and imagine grinding away on the 60 hz processor. The machines they are replacing are probably not that old, but could be close. Two orders of magnitude improvement isn't that hard to believe when you think about Moore's law.