1. An experiment in Artificial Stupidity.
2. A few beers short of a six-pack.
3. Dumber than a box of hair.
4. A few peas short of a casserole.
5. Doesn't have all his corn flakes in one bowl.
6. One fruit loop shy of a full bowl.
7. One taco short of a combination plate.
8. Cranially challenged.
9. All foam no beer.
10. The cheese slid off of his cracker.