The ALS #icebucketchallenge involves people nominating their friends to have a bucket of ice-cold water poured over them. It's all for a good cause, of course - and everyone from celebrities to six-year-olds are getting in on the act.
But if you think that 'having a bucket of water poured over your head' sounds like quite a straightforward thing, then you'd be wrong. As these Vines prove.
As you might expect, many of these fails involve the person doing the challenge ending up with a bucket whacking their head. But sometimes it's the thrower, not the throwee, who comes a cropper...