I just hooked up a new computer sound system using the Sound Blaster Audigy 2 Platinum and Monsoon PlanarMedia 14 speakers. The speakers were $140 and the card $175. The Monsoons sound great. The midrange is clean and open, good extension in to the high range, and they even image well. The sub will need a little work in placement, but I've only had the system for two days. Give the planars about 24 hrs breakin. These speakers sound great at low typical listening levels, but they sound even better cranked.
This combo is vastly superior to minisystems such as the Denon DM series, which I have in my baby girl's room. I probably will throw a PC based system using Monsoons up there and tie it into the home network and just use wave files on the server instead of a CD player.