I have the same problem with a friends computer. It's a cheap dell dimension 2400. It has a place on the mobo for a AGP slot but, It looks like it was just left off (thank you dell). So I was thinking about this one.
He dosen't game. Just the ususal internet surfing. But he really dose need some kind of video card, and he's a little limited on funds. Dell sold him the damn thing about 6 months ago and it only came with 128MB of pc2700 ram. How cheap is that.