Kilt
One wants to stay drunk all the time and the other doesn't want to pay the tab.
Look under his kilt, if it's a quarter-pounder, he's a McDonald.
For Fundsies! I made that one up yesterday so I really hope nobody has heard it before.
Gator-raid. <3 edit: Learned the difference between a crocodile and alligator.
The codpiece he made out of his girlfriend's face.