A Russian weapons company is hot on the trail of the ultimate super-soaker: a portable water cannon that has enough force to lift you off your feet. Special Materials Ltd, a St Petersburg company, is researching the idea of a “non-lethal weapon based on electro-hydrodynamical effect,” which is basically a short, sharp electric shock hidden in a jet of water. The resulting blow, however, is more sack of rice than baseball bat, meaning that the chance of serious injury is more remote. Well, that’s what they say.