A company in the UK is working on a multithrust rocket/launch vehicle that would be reusable. It mixes a super-cooled jet engine with a rocket booster. For once you get beyond enough air pressure for the jet engine.
Something like this, that's reusable, would allow small (but larger than cubesat) payloads into orbit for what should be a reasonable price. 200 launch lifetime on the vehicle is the plan.
Seems like a really interesting idea. For now I've got my money on SpaceX in terms of decreasing the cost to orbit first, they have the hardware already up and flying, and it's a bit less exotic so the engineering issues may be more well understood.
I agree, I think SpaceX will have re-usable rockets with the Falcon 9 long before this is working. But I believe you could extend the jet-powered-rockets to larger launch vehicles than you could the tech in the Falcon 9. Plus, the tech might be able to be extended to have cheaper super-sonic flights. But that's long ways down the road.