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Yeah, exactly, except someone who is handy could just get a short USB extension cable, strip back the outer jacket, expose the data pair (white and green twisted pair, I believe) and just cut them, then put heatshrink or electrical tape over where you modded the cable and you're done. Would cost you less than a dollar and take all of 10 minutes of your time.

I've done pretty much exactly that before, although there was a couple additional steps involved.

This was way back when the iPhone 3g just came out, and I was annoyed that most (real) USB chargers would do nothing more than connect the GND and +5v pins, which by USB spec is how the charger states it only has 500ma available.
To inform a device there is more amperage available, the USB spec states you need to have voltage on the two data pins.

The iPhone 3g could suck down up to 1000ma if available, which involved having +2.0v on one data pin, and a bit more on the other data pin. (+2.75v going by the link I found below. Sorry, the memory isn't too good these days)

I had a USB extension cable laying around that had a normal USB connector on one end, and a small weighted plastic base on the other end with the jack. It was intended to sit on your desk and let you plug in flash drives and be all pretty and convenient I think.
But to me the plastic base was the perfect place to solder in the two resistors between +5v and the data pins and keep all the ugliness out of sight.

The cable was something like this, although not the exact same model:
http://www.amazon.com/StarTech-5ft-Desktop-Extension-Cable/dp/B001K9BFB8

Here is a lookup table of resistances/voltages needed on the two data pins to signal various amperages:
https://www.voltaicsystems.com/blog/choosing-usb-pin-voltages-for-iphones-and-ipads/

Doing the soldering free-hand instead of digging up some perfboard made it take about 15 minutes, so you are pretty spot on.
I already had the parts laying around so didn't cost me anything, but that USB cable on amazon above was just the first result I found so I'm sure isn't the cheapest available, but even that is only $7.

Since then the "USB Condoms" other people have been posting about have dropped in price to about the same as building one yourself, plus they look a lot slicker and professionally made, and quite short compared to my 3 foot monstrosity, so I just purchase them now.

Not only does such a device help protect your hardware from the unknowns out there, but in the case of Apple connecting an iOS device over USB would auto-launch iTunes, an annoyingly long and most of the time unwanted process just to get a bit of recharge.
There have been other devices in the past I remember doing similar, auto running some software when the computer detects it. Totally annoying when one is capable of running programs on their own when needed :P

Thankfully Android never went down that path, but even there a USB condom is useful as the devices usually show up as a flash drive with your camera pictures on it which could be copied from you unwantingly, and a few models I have seen expose this as read/write!
At work I have group policies set to deny read access to any "\\\\.\\autorun.inf" file (aka that file at the root of any drive path) as well as to log to a server the fact explorer.exe tried to read one along with the exe name it tries to run.
A co-workers Android phone got infected by Windows malware we discovered this way, as some infected PC copied an autorun.inf and a [random-letters].exe to his phone, to attempt to infect other Windows PCs it got connected to.
Obviously the phone itself wasn't infected, and as he mainly only plugged the thing in at home (Linux) and at work (Windows yes but with the above GPO), and so he never noticed it was playing infectious carrier to anything he plugged into.

TL;DR - Always be safe and wrap yur wire!

This this this.

I'm thinking about a bag similar to what is offered by Voltaic Systems, but with wireless charging instead.

I bike and wear a backpack, and have been looking at rolling a custom thing from some of Voltaic's parts, and to think that if there was wireless charging capability, I would never have to worry about my devices bouncing around in my bag while connected to a laptop or battery to charge.

Someone build this and let me test the prototype =).

oops.. ctrl+v wrong link. Here's the Voltaic

There's no need to have a fast, high powered solar laptop if the goal is just to have a solar laptop.

And there's no need for a laptop that actually works when you can make one out of cardboard.

As for solar-powered laptops, there are elegant solutions out there already but they are pricey.

By "loser", you mean "stylish loser", right? You sexy beast, you.

Those panels are way too small and badly positioned to be of any use. It also sounds like a scam, it's way too expensive. Solar panels don't cost that much.

I own an older model of this solar backpack and I'd say that anything smaller than that wouldn't be very useful. In my experience it comes very handy (for somebody who heavily uses a phone for music, web browsing and talking), but it is still limited by the panel. The backpack charges an internal battery and can charge a smartphone or music player. Most people just don't have anything smaller than that.

Also as it's a backpack it's always possible to place it near a window or outside of the shadow, which would be rather difficult with a pair of pants. And it's a very nicely made backpack too.

I think solar clothing could be quite awesome, but it'd have to be entirely made of a flexible solar panel, and not just have a tiny one glued on somewhere.

There are also solar bags from Voltaic in messenger and backpack format. I haven't tried them either.

I forgot to add a couple links:
*More portable panels
*Solar backpacks

At 4W the backpack isn't going to do you any good for a laptop, but could help with a cell phone or PDA in good sunlight.

Cool! I want an external small solar panel for my laptop. Since I travel a lot and charging sucks, a small solar panel for laptops would be nice. Or better - make the entire laptop casing made of photovoltaic cells. Added to that, I look forward to see pizoelectric crystals being implemented as well.

There are companies that make backpacks with solar panels: Voltaic Backpack.

If you're going to be hiking away from the mains for a long while, then investing in a backpack with a solar powered battery charger might be a good idea. The bags on the linked page generate about 4W, which should be enough to trickle-charge a camera battery (although it depends on how many shots you are taking.

Here you are: Voltaic Systems. Use a standard car charger to connect the battery pack to your electronic equipment.

There are many more bags that have solar cells imbeddeded in them that are available for purchase right now. and important one is http://www.voltaicsystems.com/ Voltaic systems. There are plenty others as well. The innovative part of this is using the lighted material as the floor of the bag, not so much the solarcells themselves.

This page has solar backpacks and messenger bags that are already available:

http://voltaicsystems.com/

Some suggestions for keeping your gear charged up... Portable solar panels: http://www.moderntradingpost.com/powerdock/ and Voltaic backpack with solar panels: recharge small devices with solar power (not enough juice for laptops) http://www.voltaicsystems.com/

This solar powered hotspot is $1,000. Maybe an alright price for a consumer product, but a little much for something you'd build yourself, here's a cheaper solution:

$189 - Gum Stix Connex 400xm-bt, a small xscale system running embedded linux
$25 - CFstix, an expansion board for the above system allowing connection of Compact flash cards
$70 - Netgear MA701 802.11b Wireless Compact Flash Adapter
Subtotal: $284

That ought to be a good replacement for the junxion system in this case, for 40% of the cost.

As for the solar power, you might want to use the same Voltaic Systems bag they used in the article, but you could deck out a bag you already have with solar panels and such and it might be a little cheaper. Hell, if you wanted you could put their solar panels and batteries in your bag, they sell them seperately!

This thing, as made in the article, costs over $1000, I would have thought a project slashdot would link to would have somebody rigging up their own solar panels instead of paying $230 for a bag with solar panels on it and setting up their own system (mini itx or some such) instead of paying $700 for a Junxion Box.