Weird computer architectures

Quantum computing is getting quite the buzz, but there are other bizarre computer architectures bubbling and buzzing away in research laboratories. New Scientist compiled a survey of the "Ten Weirdest Computers," from reversible chips that recover energy usually lost with each operation, to magnetic (NMR) computing that leverages the dynamics of molecular interactions, to slime mold computers. From New Scientist:
Toshiyuki Nakagaki at the Institute of Physical and Chemical Research in Nagoya, Japan, has shown that slime mould can work out the shortest route through a maze.

In his experiments, the masses of independent amoeba-like cells that act as a single organism would initially spread out to explore all the possible paths of a maze.

But when one train of cells found the shortest path to some food hidden at the maze's exit the rest of the mass stopped exploring. The slime mould then withdrew from the dead end routes and followed the direct path to the food.