Autoplay using USB as attack vector – disable in Windows XP

My computer got a malware infection which eventually installed an Internet worm. How did this happen? I use my USB memory stick as backup storage for when the Internet is not available (or simply is slower to use). Over the past few days I have used my USB memory stick (8gb Dane Electric, $20 retail in Victoria, BC, Canada, thank you) in three different locations including a computer at a school I teach in, an Internet cafe (for printing), and a supplier's desktop (where I am pretty sure I got infected).

How to fix

Simple: disable autorun for all drive letters. This way the autorun.inf is not initiated, which launches what looks like winamp file of some kind, but that then opens up some websites and downloads the Internet worm.