I don't know about you, but when I have slingshot-paintball-fights with my friends, I generally wish they could be a touch more video-gamey. Filmmaker Andrew McMurry agrees, putting together this a live action film that that weaves normalcy with a convincing digital overlay to give things a distinctly video game feel.
Four friends dash into forest cover for a game of slingball, where "missing" your target often gets a kill anyway thanks to explosions, pits, spikes and traps. In a nice touch, these warriors queue up their paintball-types at the outset of the film, and the firefight keeps tabs on that order.
The inspiration for this wasn't really Modern Warfare or Team Fortress so much as "video games as a whole". For some more specific homage from the same creators, check out their take on the Mario universe.