A dare where you have to eat 6 saltine crackers in 60 seconds without drinking anything, and all the crumbs must be eaten as well. Although it sounds easy, it's actually really hard because the salt and crumbs dry out your mouth and are hard to swallow and you can't drink anything to help you out.
You: I dare you to take the saltine cracker challenge!
A dare where you are challenged to put ice on your hand with ice and keep it there until it melts.
"What's that mark on your hand?"
"It's the burn I got from the ice challenge."