Klipsch Promedia computer speakers are highly regarded. The highs are superb and the bass rumbles. Your neighbors might not like you if you crank up the volume. A cheaper alternative but one that also performs well is the Logitech Z2200. Both speakers feature 200 watts of RMS power. I think Logitech has discontinued the 2200s and replaced it with the Z2300. People say that the Z2200s are better than the Z2300s, so buy those if you can find them. If money is not a concern, then go with the Klipschs.

Klipsch Promedia computer speakers, I agree :)