Actually, Sloot encryption was a real-life system, said to be able to convert a three-hour movie into a file size of eight kilobytes of data - and, this was back in the '80's and '90's.
A combination of solar panels and Farnsworth Fusors. But, some negative mass must be used. For a bar-shaped drive powering a ship, one the mass of Jupiter is needed; for a ring-shaped one, you only need one the size of a Voyager Probe.