May favourite player, too. Definitly worth recommending.
Very slim, very stable, and can cope with almost any format you throw at it.
Another small, but for me quite valuable feature:
When you're using two monitors, VLC (DVD-)playback works on both monitors - several other players only work on the primary monitor.
(Means I can play GalCiv2 on one monitor while watching Babylon5 on the other for the nth time. )