A few years back I bought a few lengths of pipe insulation from the local Screwfix. The metre-long foam tubes, slit down the length of one side so you can push

A few years back I bought a few lengths of pipe insulation from the local Screwfix. The metre-long foam tubes, slit down the length of one side so you can push them over 15mm copper pipes. The girl working there asked, out of interest, what I was buying them for. I started to say, pipes to the radiator are running directly behind the fridge... she interrupted to say "oh, actually for insulating pipes? We had a couple in here last week buying them for their kids to use for sword-fighting". Sounds like a brilliant idea to me! Cheap enough to easily replace when they break. And the adults can easily nick them off their kids and have just as much fun using them to beat the shit out of each other, and they don't even hurt.