1. A few clowns short of a circus.
2. A few fries short of a Happy Meal.
3. An experiment in Artificial Stupidity.
4. A few beers short of a six pack.
5. Dumber than a box of hair.
6. A few peas short of a casserole.
7. Doesn't have all their cornflakes in one box.
8. The wheel's spinning but the hamster is dead.
9. One Fruit Loop shy of a full bowl.
10. A few feathers short of a whole duck.
11. One taco short of a combination plate.
12. All foam, no beer.
13. The cheese slid off their cracker.
14. Body by Fisher, brains by Mattel.
15. Couldn't pour water out of a boot with instructions on the heel.
16. They fell out of the stupid tree and hit every branch on th way down.
17. An intellect rivaled only by garden tools.
18. As smart as bait.
19. Chimney's clogged.
20. Doesn't have all their dogs on one leash.
21. Doesn't know much but leads the league in nostril hair.
22. Elevator doesn't go all they way to the top floor.
23. Forgot to pay their brain bill.
24. Their sewing machine's out of thread.
25. Their antenna doesn't pick up all channels.
26. Their belt doesn't go through all the loops.
27. If they had another brain it would be lonely.
28. Missing a few buttons on their remote control.
29. Receiver is off the hook.
30. Several nuts short of a full pouch.
31. Skylight leaks a little.
32. Slinky's kinked.
33. Surfing in Nebraska.
34. Too much yardage between the goal posts.
35. No the sharpest knife in the drawer.
36. The lights are on but nobody's home.
37. 24 cents short of a quarter.
38. A few sandwiches shy of a picnic.
39. Doesn't have all their eggs in one basket.
40. One neuron short of a synapse.
41. The Death Star plans are NOT in the main computer.