How about the classic line from the blues brothers:
"We're on a mission from god" (perfect for beer runs)

I recently used the speech from the same movie before leaving on a trip to go to Cabela's in Hamburg Pa..

"We have full tank of gas, half a pack of cigarettes, it's dark out, and we're wearing sunglasses...Hit it."

Toolmaker

In a similar vein:

Frankly my dear..... Rhett Butler to his wife / Gone with the Wind

Good for indicating you are tired with this 'game'

I see stupid (dead) people /Sixth Sense...and they are all around me

Own customisation

When 'us engineers' have had to endure another meeting with project managers and architects

To express irony about a situation:

Top of the world ma/ James Cagney

A quite clever one, summing up lifes' compromises:

Is it worse to be looked over rather than overlooked / Mae West

"How's this gonna work, if you don't mind me"

Kevin Costner to the good looking women co-star in Open Range (I think.)

I like to use it on my wife from time to time.

"It's a rifle, Hughes..."

from Colour Sgt Bourne in "Zulu".

Use it as an answer to a question whose answer is obvious.