I tend to use a Edirol UA-25 (although there is now a Edirol UA-25-ex with an analogue compressor which looks quite nice) priced at about £125 and £175 respectively. Not sure if the newer version is really worth it though.
I've used the UA-25 on Linux, Windows XP, Windows Vista and OSX in the past with no troubles. It's only 2x2, with no spare stereo input but along with the XLR/TRS inputs, it also has a Hi-Z button for guitar direct connection, S/PDIF optical I/O ports and the old style MIDI I/O ports. I can't really say much about it other than it's given very decent recording wuality for the price and it just sits there doing its job, and it's survived being hefted about the place too.