Like The AlmightyBeev, I perform 'experiments' as part of my job.
But as I am a classroom science teacher, they are largely all in labs, rather than in my home. Having said that, one of the things I like to do is simulate 'playing with fire' situations in the lab, and demonstrate how not to react to them. It's almost like some of the stuff the kids learn could actually be useful!

For instance, what to NOT do when you have been playing with a candle, and it has started to burn out of control a bit...
www.youtube.com/watch?v=4kemgB_o_j4

I also (as a stupid trick to show off to 11-year-olds) taught myself to eat fire. www.youtube.com/watch?v=es3iw_d39T0 Hint, it's just cotton wool, but make sure you get all cotton and not the stuff with nylon in, or it melts into your face and big tears happen.

Anyway, when kids ask me how to do this, I tell them (very truthfully) that it is not as safe as it looks. For instance, when I was learning how to do it, I burnt off half of my movember moustache. Then when I was teaching a fellow science teacher, he burnt off half of his moustache. Then when I was trying to teach my brother, he burnt his fingers, dropped the burning ball of cotton wool, and burnt a nice hole in my carpet. The bell-end.
(Serotonicity was a naughty boy on..., Thu 16 Aug 2012, 0:31, 2 replies)

Mr Bell,
Lol, Bell. Like the end of a Willy. Lol!
( Windy Pig I'm naturally quite suspicious about the moon., Thu 16 Aug 2012, 7:49, closed)

It took a good 2 years into my career before I heard a kid call me "bell-end". He was most put-out when I found it funny. But even more put-out when I still gave him a detention!
(Serotonicity was a naughty boy on..., Thu 16 Aug 2012, 10:41, closed)