Two blonde roomates go to the petshop and come home with pet mice.
Upon debating how to tell them appart one blonde suggests they cut off the tail of one of the mice. It seems like a great idea so they go ahead.
That night the mice are talking and one says to the other "wow, thats cool you don't have a tail." "I know!" "I wish I didnt have a tail." "Well you can, just chew yours off." So the mouse does.
The next day the blondes check on the mice and find neither of them have tails. So they decide to cut off the left front paw of one of the mice.
That night a similar conversation takes place between the mice adn in the morning the blondes find both of their mice three-legged with no tails.
This continues until one morning neither of the mice have any legs or tails.
"This is getting ridiculous!" one of the blondes finially exclaims,
"I'll tell you what, you take the black one and I'll take the white one."