Shoutbox

If you're in the US. you can buy a block of dry ice at Walmart.  I've played with dry ice bombs before, and as Cookie said, they can be VERY dangerous.  A friend of mine got hit with a bottle cap when we were playing with them, and it left a nasty and very painful welt on his chest.  He ended up having a bruise the size of half a dollar bill.

Though, it was fun.  Try tossing a whole block or two into a swimming pool.