Well, a friend has the Behringer MS-20. They sound really pretty good nearfield at reasonable volumes. They also have 2 digital inputs (of which I think you can only use one at a time) and 2 analog inputs. They seem to be available at Amazon for about $100. The MS40's aren't much more but have a larger woofer.
Mark has some Mackies that he likes. I don't know which ones. He seems to like them and - gawd help me - I trust my brother's judgment. M-Audio also makes some inexpensive ones, but I don't really know anything about them. I am using an M-Audio adapter between my computer and BFD and it works like a charm.