AHHHHHHHHHHHHHHH (edited for inappropriate language. )
I'm with Peter - I'm 100% sure I've seen the movie in question, but can't pinpoint it. Watch, I'll remember it at about midnight and I'll have to get up, get out of bed, come downstairs, and post the answer.
Is it the bit when Arnie reveals himself to himself (if you see what I mean...)
Guess it's my turn now. Can't choose my usual one, as Zeph appears to be as much of an Arnie / Stallone fan as me, so I'll make it a little more obscure (but not too obscure, of course .
Here's one that a mate's been coming out with quite a bit recently: