Sorry if these are repeats, I didn't read the entire thread:

You look like a bag of smashed a$$holes.

More frustrated than a moth in a light factory.
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I got this one so many times from my Mother..."You'd better straighten up and fly right"

And my grandmother, never to be outdone, "There's two kinds of Smart: Smart and Smart Alec".

I was the second one every time that would be forced out of her mouth.
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Nervous as a cat in a room full of rockers.
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http://www.youtube.com/watch?v=bx1Jz3IJCo8
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Got some appropriate ones:

Colder than a witches caress.
Colder than a landlords heart.
Colder than a room full of ex-wives.
Colder enough to freeze the nuts off the Guy Lombardi bridge.
Cold as a mother-in-law's kiss.
Colder than a welldigger's ass.
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Old kitchen manager in a restaurant I used to work at used to say:

"Boy, you look like a 3 legged cat trying to bury turds on a frozen pond."
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You better check yourself before you wreck yourself.

Standing out like a turd in the punch bowl.
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