A rat in the grain is worth two in the woodpile.
A rat is just a mouse with an MBA.
A rat is a good judge of cheese.
The rat race is over. The rats won.
A rat's god is cheese.
Life is like a rat race, but with more cheese.
A mouse in time saves nine.
The best-laid plans of mice and men often go awry.
Even a blind squirrel finds a nut once in a while.
I've been called many things, but never a rat.
If you can't beat them, eat them.