A Few Bricks Shy of a Load...
 

Do you have any unique sayings you use when you want to say that someone is nuts (i.e. "not playing with a full deck") or not too bright (i.e. "not the brightest star in the solar system")? I know there are some funny ones out there, but I can't recall them at the moment.

One sandwich short of a picnic

Not the brightest crayon in the box. His elevator doesn't go to the top floor.

not the sharpest knife in the drawer

My sister likes...
 

"A few fries short of a Happy Meal."

I was gonna pick that one!!!

I just either tell it like it is (I use to joking call a friend a ditz b!@%#..., they use to call me know-it- all b!#$@; cant help it if im right all time :p ) or say they're loopy or go woo-hoo.

Not the brightest bulb in the box
Not all there
More cuckoo than a cuckoo clock
You are PROOF POSITIVE that CRACK KILLS
You are proof positive that family members should not have sex.

when i'm feeling particularly vicious (or the person is that dumb) i enjoy the phrase "Poster Child for Birth Control"

Sharp as a marble!

One of my favorites--and it really goes for anyone or anything that is pathetic

"They've hit rock bottom and started digging."

or another good one

"They're so dumb they're just barely able to keep a grapefruit from rolling uphill" but the problem I've run into with this one is that people have to think about it and if you just throw in to a conversation people won't get it.

It's a little old but how about, "The lights are on, but nobody's home."

When I really want to be subtle (joke) I say, "He/she is dumber than a brick."

Or, "If his IQ was 3 points lower, he'd be a plant."

These are funnnnnny...thanks to everyone who posted already and made me laugh! :D My friends and I are notoriously snotty when it comes to guys and intelligence. We just CANNOT STAND dumb guys. usually not too much of a problem though - I'm in law school now, and the rest of my close friends are too or in med school or vet school.

Dumb guy in bar trying to be original: "So, uhhh...what's your major?"

Me: "I'm in law school"

Dumb guy, panicking "ummm...ok...ummm...I, uh, have to leave"

it's a great system - they pretty much weed themselves out.

Here's my contributions:

"couple beers short of a six pack"

"better seen and not heard"
(this is my friend's saying for guys that are really pretty, but just embarrassingly stupid, which becomes apparent whenever they try and talk)

"world's greatest argument for population control"

"low-riding brain"
(again, my witty friend for the twits at the bars who are only capable of thinking with the "brain between their legs")

"Warning: testosterone causes mental retardation" (for the thick necked gym junkies who think you'll fall in love because they have biceps)

I don't want anyone to think I'm bashing guys here - just the stupid chauvinistic ones. Guys that are jerks deserve to be laughed at, in my opinion.

Duhhhhhhh........
 

Not the brightest bulb in the chandelier.

What a num-nuts.

Dumber than a box of mice.

And I will never forget my sister's comment on Lou Diamond Phillips...."He looks SOOOO good - then he opens his mouth." :p

33...

You reminded me of a variation of one of yours...

"Dumber than a box of rocks."

My mother described my cousin's ex-husband's as having "the personality of a dead rock".