Try one with wasabi

I'd like to see this doing the rounds at a kaitenzushi counter.

Its purpose is mysterious, but a fuel cell-powered robot fish has been developed by Osaka City University professor Tomoyuki Wakisaka, Nikkei Net reports.

The prototype moves by swishing its tail with power produced by mixing oxygen with hydrogen in an internal system that makes use of powdered calcium.

The novel approach would allow the little minnow to swim much longer than robot fish powered by ordinary batteries. The professor is also experimenting with magnesium to produce hydrogen to allow it to swim for three hours straight. A practical fuel-cell fish may be ready in two or three years.

Best served fresh.