Since the whole point of this instructable is using repurposed parts, it won't be exactly step by step. Instead I'll guide you through finding and choosing parts, and testing them. Then you can apply it to your project as necessary.
EL wire is a copper wire covered with a phosphorescent coating. 2 extremely thin copper wires are wrapped loosely around this coated copper wire, and the whole thing is covered in plastic. When AC (and only AC) current at about 90-130 volts is passed through the outside and inside wires, it excites the phosphor, and the wire glows like a neon tube. It's very, very cool stuff.
Generally, you need a driver to convert low voltage DC battery power in high voltage AC power. These inverters are available online, but there are a few problems:
1. They break. Quite often.
2. They aren't expensive, but they aren't cheap either.
3. You can pretty much only get them online.
4. They require batteries.
I wanted to put EL wire all over my bike for Burning Man this year, but I wanted to light it with pedal power. No worrying about charging or hauling batteries, just pure muscle power. I had an old stepper motor lying around and I remembered that they ONLY produce AC current. Usually you have to rectify it to DC to use it. But I needed AC! Could it be possible to hook an old stepper motor up to light EL wire with no driver all? The answer, it turned out, is yes, and not only that, it fades on and off with speed, and can even change color (slightly) as the frequency of the AC signal changes. SCORE!
Here's a video of the final project in action. This is before I got the wheels lighting up too. In the first few seconds of riding, you can see the color shift from Green to Blue, because of the change in frequency as I speed up. Also, I should warn you that this is on my swing bike, which has two pivots, so the video may be confusing if you've never seen a swing bike in the day-time:
Now, on to the disclaimers:
First, this instructable deals with electricity. Be sure you know what you are doing. I gave myself a few nasty, though not life-threatening, shocks along the way.
Second, sending unregulated power through EL wire could short it or shorten its useful lifetime. It's importand to size the output of your generator at speed to your transformer so you don't damage the EL wire.
Step 1: Parts list
A Stepper Motor
An old cell phone charger
A Rheostat (optional but highly recommended)
In each of the following steps, I'll show you what these parts do, why, and where to find them cheap.