"I don't like you. I think you're a fake acolyte. The sound of your piss hitting the urinal? It sounds feminine. If we were in the wild, I would attack you. Even if you weren't part of my food chain, I would go out of my way to attack you. If I were an Eldar and you were a squig, I would teleport all the way to your part of the greenskin horde and freaking EAT YOU! And then I'd bang your squig girlfriend."
"Okay, first off - wait, that's disturbing."
Just finished watching The Other Guys and it was funny as hell. Of course, a 40K crossover came to mind eventually: specifically Dark Heresy, due to the shenanigans you could get up to in there, what with being a normal human in a universe of giant green alien wrestlers and army-annihilating technoaliens with plasma rifles.
Here, Will Ferrell would be the Techpriest who somehow became a pimp in high school, and Mark Wahlberg would be the Guardsman who plays spider solitaire at work. Together, they would expose Ershon as a money-grubbing scammer who - wait a second. Ah, screw that, never put that much thought into it anyway.
Since this is Dark Heresy, it woudn't be complete without a psyker accidentally summoning a daemon.
"What the hell is this?"
"It's my ride. It's a Sentinel."
"I feel like we're literally driving around in a vagina."