What to throw at someone besides eggs?

So friends and I are doing a take on a challenge. But, in the original, when you get something wrong, an egg is thrown at you. I've heard and seen how painful those can actually be so we were hoping for ideas of replacements. I thought of water balloons but this would be outside and where I live it is very cold right now and so it'd be entirely too freezing. So please, any ideas? (sorry this is such a weird question)