New Scientist reports that an Air Force study suggests using an electromagnetic catapult to launch satellites into orbit or rocks at other cavemen. Gee…where have I heard that before?

Proponents of the idea say it would be much cheaper than conventional rocket launches. But critics warn that the technology would be difficult to develop and that the intense g forces experienced during launch might damage the very satellites being lofted into space.

So, no, that wouldn’t work for people, except as a means of capital punishment.  Heinlein didn’t event the mass driver, but he suggested a great use for it: to fire raw materials into space. That would be handy when building structures in space.

Of course, Heinlein also envisioned using it as a weapon, which can easily be an application of this device too. Still, nifty.