A coiled cable is easier to manage than a long cord that gets tangled up. If that's what you want with your USB cable, Instructables user pizzidave has a quick way to do that with just a pencil, tape and a blow dryer.
Starting at one end of the pencil, tape down one end, leaving about five inches of slack. Wrap the cord around the pencil, leave another five inches of slack and tape down. Your wrapped part should be tight and not too pulled.
This is what it should look like:
When that's done, use your blow dryer on high to heat up the plastic until it's warm. Make sure you get every bit by rolling the pencil around as you apply heat. Then, let it cool down completely before removing the pencil from the coiled cord -- don't try to unwrap the cord itself.
One word of caution: There is a chance that this will damage your cable. While there's no solid data I could find on this subject, general consensus on the internet seems to be that the bend radius of USB cables should be about 3cm, and this method definitely bends it more than that. So if you want to try this hack, use a spare cable first -- you're bound to have one lying around somewhere.
Coiling a USB power cord [Instructables]