Here’s a great USB DIY Sound Card that NEEDS NO XP drivers. It’s plug-N-play. For a DIY project, very impressive and everyone should make their USB DIY “driver-less”.
Make a sound card is no more a complex issue. If you use great IC PCM2702 from BURR BROWN / Texas Instruments you can create a fully functional USB sound card. This sound card can be powered from USB port and has one stereo output. You don�t need to install any driver for Windows XP and Vista, because they are already inside. This is really plug and play.
Few months ago I have seen USB sound card called Alien DAC. The construction on the project web page inspired me to build this thing also.