Charles Chase and his team at Lockheed Martin's "Skunk Works" made quite a splash recently by announcing that they are attempting to develop a truck-trailer-sized 100-MW fusion reactor-to be ready for operation in just a few years!
Chase discussed the compact fusion reactor concept at a recent Google "Solve for X" talk:
Not as compact as this:
But fusion power for 100,000 homes as compact as this:
Lockheed Martin is trying for an operational prototype by 2018, a commercially available system by 2023, and the ability to meet global baseload energy demand by 2050...