There was a recent thread I lost about some kind of small-scale sound system or something and maybe in the same thread was mentioned not to go with the 'cubes'. When I started out in this tiny room I thought I could get away with a 'cube' system and went bingo with the Klipsch Cinema 6 system consisting of 4- RSX-3's and an RCX-3, plus an Infinity PS-10 sub...
The Klipsch's are very versatile to be mountable on a vertical or horizontal surface with keyholes on highly rotatable pedestals and the sound is very clean and coherent at 4lbs each.
There is an RSX/RCX-5 also. I got the silver 3" ones at 1/2 price for about $350.
The receiver/amp stuff would require individual research, and do the homework unless you want to get stuck with a crumby distortion box.