My family does this every year as well. We have a great mix of awesome and gag type gifts. The chance to steal gifts + a large Italian family + alcohol = a crazy fun Christmas.
At ours you usually have 2 categories of gift givers. 1-who can bring the absolute best gift for $50 and 2-who can bring the best gag type gift.
This year I bought an unprocessed gold nugget. Don't get me wrong, its small but I think it will go over big.
A good bottle of booze is always good.
The new toy "duck hunter" is hot this year and looks like fun
depending on the age and type of family I have seen:
weapons (Chinese stars, butterfly knife, pepper spray, taser)
a bag of weed
gift certificate for a good car wash
50 scratch offs
a jersey
a book (if there are any family jokes this could factor in)