One of the most FUN Christmas parties my parents had a few years ago they had a "Chinese Gift Exchange" (not sure why they called it, and it's probably got other names). If I remember correctly this is how it worked:
Everyone brings a wrapped gift, gag or real, and places it under the tree. Each person is given a number upon arrival, drawn from a hat or 'assigned'. At gift exchange everyone goes in numerical order to choose a gift from under the tree. Unwrap it for all to see. The catch is that if someone likes the present that a previous person unwrapped, they may forfeit the under-tree gift choice, and take a previously unwrapped gift. Then the person whose gift is taken picks another under-tree gift, unwraps for all to see. One person can only have their gift 'taken' 3 times. It works best when there are LOTS of people.
It was hilarious watching everyone get sort of mirthfully ruthless in their gift 'trading' and scheming to get what they really wanted. Everyone left with something though, and all had a great time.
Happy Christmas!