Twisted logic

If you've heard of fusion energy, you've probably heard of tokamaks. These doughnut-shaped devices are meant to cage ionized gases called plasmas in magnetic fields while heating them to the outlandish temperatures needed for hydrogen nuclei to fuse. Tokamaks are the workhorses of fusion—solid, symmetrical, and relatively straightforward to engineer—but progress with them has been plodding. Now, tokamaks' rebellious cousin is stepping out of the shadows... By Daniel Clery.

http://www.sciencemag.org