When we have to do repairs around the house and are looking for the right tool, we often find ourselves quoting Guy from Galaxy Quest:
"Look around you, can you form some sort of rudimentary lathe?"
Or when someone promises something and it doesn't work out, or does something deceptive (especially around Christmas) we'll jokingly tease them with this line about the fake mall Santa from Elf:
"You sit on a throne of lies!"
A big one is The Princess Bride and:
"You keep using that word. I do not think it means what you think it means."
We use this quote from Old School a lot to congratulate someone on a good job:
"You're my boy, Blue!"
And of course Hudson's big line (one of many) from Aliens when you're beaten while playing a video game or a game on TV is done (or one side has obviously won):
"Game over, man! Game over!"
We frequently quote Ghostbusters, The Big Lebowski, Caddyshack, Austin Powers, Wayne's World, the Star Wars films, the Star Trek films, Godfather, Scarface, Anchorman, The Other Guys, Office Space, Die Hard, Airplane, and Monty Python and the Holy Grail.