A few Bathurst Freaks short of the SuperCheap Auto 1000
A few Beers short of a six pack
A few Bits short of a Byte
A few Cents short of a Dollar
A few Drops short of a puddle
A few Drivers short of a Racing Team
A few Elvis' short of a Mental Institution
A few Freaks short of a Marylin Manson concert
A few Hairs short of a Comb Over
A few Kangaroos loose on the top Paddock
A few Legs short of a Chair
A few Rolls short of a bread shop
A few Sandwiches short of a picnic basket
A few Scientists short of a Nuclear Testing Facility
A few Snags short of a barbie
A photographic memory but with the lens cover glued on
A prime candidate for natural deselection
A room temperature IQ
Both oars aren't in the water
Bright as Alaska in December
Couldn't organise a Fart in a Bean Factory
Donated his body to science before he was done using it
Fell out of the family tree
Got a full 6-pack, but lacks the plastic thingy to hold it all together
Got into the gene pool while the lifeguard wasn't watching
He aint wired up right
He can count his IQ on his hand
He couldn't bluff his way through a Poker round with 5 Aces
He does'nt play with a full deck
He has'nt got a full ticket
He's a rocket on Rails, but his wheels lack the flanges to keep him on the track
He's about a sharp as a kilo of wet leather
He's been wading in the shallow end of the gene pool too long
He's come out all guns a blazing, but the pistols are still in their holsters
He's got a V8 under the hood, but the timing belt is out
He's one brick short of a building
He's so dense, light bends around him
He's only a 25 Watt'r
His Brain flies south in the Winter
If brains were Dynamite, he couldn't blow his nose
If brains were taxed, he'd get a rebate
If he had a Brain Cell it would be lonely
If he were any more stupid, he'd have to be watered twice a week
If you gave him a penny for his thoughts, you'd get change
If you stand close enough to him, you can hear the ocean
Lets get the ball rolling
Not the sharpest Knife in the Block
Not firing in all Cylinders
Some drink from the fountain of knowledge; he only gargled
Takes him 1 1/2 hours to watch 60 minutes
The Elevator doesn't go to all the way to the top floor
The lights are flashing, the boom gates are down, but the train, she ain't coming
The Lights are on but nobody's home
The Stable door is closed but the Horse is gone
The Tree doesn't go all the way to the top Branch
The Train's on the track, the pantograph is touching the wire, but the drivers asleep
There's one in every group
There's only half a Bun in the Oven
Two Chromosomes short of a Potato