the little powered speakers don't put out much music-wise. nothing that small can have any bottom to speak of. most subs are little and can be tidily hidden under the workstation.
creative labs and logitech are two brands that come to mind (I just bought a creative labs set). this logitech looks cool, I almost got it. it's fifty bucks.
http://www.circuitcity.com/ssm/Logitech--X-230-2-1-Stereo-System--970123-0403-/sem/rpsm/oid/115312/rpem/ccd/productDetail.do
but, if music isn't your intention and you just want powered speakers for computer sounds, web sites and the like, go on eBay. There are bazillions of people selling the speakers that came with their PC's. we're talking five and ten bucks for some. search for computer speakers.
look here, these were fifty cents with 40 minutes left to go!
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=3702&item=6735323817&rd=1
Does anyone have a recommendation for a pair of desktop speakers with good sound quality at a moderate price - say $50 or less? The PC just has the built in sound on the motherboard. I'd like to use just the two speakers without a subwofer.

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