The current New Scientist has a feature on Roton available at <http://www.newscientist.com/ns/980801/features.html>. Briefly, a Roton craft's engine spins on ascent, saving the weight of fuel pumps, and a helicopter like propeller opens during descent to help accomplish a soft landing. These and other improvements could supposedly provide an eighty percent reduction in cost/kg relative to conventional rockets.
I believe someone mentioned the Roton on this list a year or two ago. Rotary Rocket <http://www.rotaryrocket.com/> seems to have made financial, political and technological progress since then. They have raised $17 million so far, expect to raise $30 million more this year, NASA administrator Daniel Goldin likes them, and they supposedly could do flight testing next March.
-- Mike Linksvayer ml@gondwanaland.com