There might be spoilers in this thread so just be warned.
I'm watching Freddy vs. Jason right now (it's on pause in the other room) and I just go to the part where the flamin' Jason comes across the ravers in the field and a few of them are in the van escaping. One of the stoners looks like a Jay (from Jay & Silent Bob) and right after he says 'That goalie must be pissed' one of the other characters says 'Fuck the police!' In Jay & Silent Bob Strike Back Jay says 'Fuck the police!'.
And in About Schmidt when Warren meets the couple in their campervan and he brings a few beers over for dinner, you hear a flush and the other guy comes out of the bathroom. Warren sniffs the air and asks 'Is something burning?' and the other guy says 'Oh no, I just lit a few matches.' That always makes me chuckle
So is there anything nifty that you've picked up or noticed in a movie that others might have missed? Maybe it was deliberate or just a funny coincedence, post it here!