Preferibly not real player of windows media. Mostly for MP3s and other music playing in the background while I work, so if it only takes a little RAM, thats a plus.
It can rip, encode, tag in various formats and plays almost every audio format in existence. It has a simple UI, so it has a small footprint and although it packs a whole lot of features, it is somewhat less intuitive than Winamp or WMP.
Just my opinion.....but Foobar is a pain in the ***. Too simple in some areas, too complicated in others. One of the better playback programs I've heard, though.