05-03-13: Bob_reynolds
There's a gazillion choices. Budget and whether USB or analog connection from PC would prune the field.
True, but a little more information from the OP would help trim the field. E.g., how much space does he have, and what's his budget?
E.g., The AudioEngine A2s are *tiny*--about 4"x6 front and they're powered, all for $199. Contrast that with Minuet Silverlines (a great speaker), which are a bit bigger but you lose more desk space to the amp required to drive it. For bass down into the 20s you add the system-matched AE sub for $349. It's slightly smaller than a 12" cube.
AudioEngine offers many accessories such as wedge stands to hold the speakers, isolate them from desktop resonances, and point the drivers right at your head.
If he has space for bigger speakers, then the AudioEngine A5+ could do it, with a front face of about 7"x 10.75. As others have said, the bigger cabinet may reduce the need for the sub depending on the OP's requirements.
An AudioQuest Dragonfly can completely solve the analog vs. USB dilemma.
My first choice would be an AQ Dragonfly (with Audirvana or J River Media software), Dragonfly ($250), AudioEngine A2s ($199) for minimum desktop intrusion, and the AudioEngine S8 Sub ($349). That's a killer soup-to-nuts full range solution for $800.
Or you can start with A2s for $199 and add the other parts if/when you want to enhance or upgrade.
The rave reviews for the AudioEngine A5s and A2s are pretty overwhelming, and come from all corners of the audio and computer fields, from Stereophile to Gizmodo and even Fortune magazine:
A5 reviews
A2 reviews