OK, I was looking at evilmadscientist (the recent 20 millicentury article with the "use bike tubes as rubber bands" link and picture in it) and Tommi Potx's bike tube instructable, as well as cursing my busted flash drive casing, when I realized I could use an old bike tube as a new case.
EDIT: I just found that it was quite similar to thearchitect's flash drive "case mod" (right here), except in rubber, not leather. Giving credit where due.
You'll need:
A flash drive you can remove the case from
A bicycle inner tube
Rubber cement
Good scissors or x-acto knife.

Step 1: Remove.

Take the old case off of your flash drive. Or, if you prefer, you can skip this step. You can't leave the case on if your drive is a swivel-type, though.

Step 2: Slice Time, Part 1

Get out your old (bicycle) inner tube and hack off your desired length of tube. For my PNY orange 2G drive, I used an 8 or 9 inch section.

Step 3: Slice Time, Part 2

Now, take your section of tube and slice it down the middle to make a flat piece of rubber. I would suggest washing the talc out of the tube at this point. It will hinder later steps.

Step 4: Slice Time, Part 3

Now, take your new section of rubber, and slice your desired width strip of it (mine averaged out at about 1 cm). Take the extra rubber and add it to your patch kit.

Step 5: Wrap the Drive.

Take your strip of rubber and wrap it around the drive (not too tightly, however, as it may seal in heat and make the drive malfunction).

Step 6: Glue.

Now do you see why you wanted to remove the talc? Glue and talc don't work well together. Take your loose end of rubber and some rubber cement and glue it down. Simple as that.

Step 7: Needs a Lid...

Take some more bike tube and cut it into the shape shown below to fit your flash drive. If you have slow internet, it looks like a capitol "T". wrap the top line of the "T" around the plug, then glue the bottom line down over it.

Step 8: Fin!

It's done. Customize coloring to your liking with a metallic sharpie or the likes. This is my first 'ible, so constructive criticism is welcome, nay, insisted! Coming soon from me:
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