The M-Audio StudioPro 3 Desktop Audio Monitors are good computer speakers. I'm no audiophile expert, I'm just looking for decent speakers for listening to MP3s and the occasional Youtube video. These fit the bill for about $85.
The main thing that sets these apart from your usual cheap computers speakers is the enclosure. Instead of a cheap hollow plastic box they're MDF, a wood composite. They sound pretty good to me, particularly crisp in the mid to high range. Without a subwoofer cluttering your desk the bass is limited (they spec at 100Hz-20kHz ±3dB), but there's a decent bass port on the back and a booster circuit if that's your thing.
The design is functional; decent shielding, an extra aux-in jack on the front, and nice little wedge stands for pointing the speakers up from the table to your head. They're not particularly attractive but they don't look stupid either.
M-Audio makes a variety of small amplified speakers for various price ranges. I sure wish someone would just make a candybar sized small amp so I could power ordinary speakers from my computer.