Lunchbox Computers for Live Music Performances?

Dan Reetz asks: "As a PC based musician, mobility is critical. However, most laptops have horrible soundcards. PCMCIA cards like a VXPocket cost about 700 clams. A friend of mine recommended I look into 'lunchbox' style computers as a portable solution. A few searches revealed them to be quite expensive and they are hard to find used. Does anyone know of a source for used Lunchbox PC's (even just the diplay would be fine) or a better low latency/noise audio solution for laptops?"