Halo 4 has been out for nearly two months now, which means people have had a sufficient amount of time to f*ck with it.
As the community suggests more and more crazy things to mess around with, the folks at Defend the House have been chronicling them in the form of a Mythbusters-style video series. The series in general reminds me of the early days of YouTube, where my friends and I would share Halo 2 super-jump videos.
Episode 4, which was just released yesterday, goes on to confirm or deny such myths as "continuing a multi-kill after death," "sword lunging through teleporters," or the fact that an actual grenade impact can kill you (the grenade itself, not the blast!). My favorite one so far is probably the "multiple sticky detonators myth" in Episode 3.