FWIW, I bought a pair of mini Samson PA speakers (Expedition?) with stands although the speakers have that angle on one side so you could use them standalone and have them on the floor.. they were fairly inexpensive.. I think I paid about $79 per speaker and the stands are mini but sturdy and were about 100 for the pair. I was skeptical but tbh they kick ass esp in my smallish music room.. I've jammed with three friends with vocals, bass, two electric guitars and I was totally in line with their volume even at halfway and the sound was pretty decent for drums (I use my mixer to tweak the EQ somewhat). If I had the cash I would certainly buy a decent drum speaker or pair, as advised but this has done me fine (and so funny you mentioned the pc speakers, as I tried my semi-decent Logitechs way back when I had my first cheapy used ekit and yeah, they sucked big time and I probably blew them with the kick drum, hahaha, but it was a fun experiment at the time). I've also played my Alesis through my Mackie PA speakers and the sound was pretty darned good too, for my ears at least.
http://www.samsontech.com/expeditionseriesguide/Update: my particular model of Expedition shows discontinued now.. maybe you'd find some on clearance somewhere.. if budget is a concern of course, as they're not perfect by any means.. but I've taken them to a few jams and they're small and portable, saves my back.