Late last year a speedrunner managed to complete Fallout: New Vegas in an impressive 20 minutes and 47 seconds. Now, barely four months later, the same speedrunner has managed to shave nearly a minute off that time, coming in at 19 minutes and 48 seconds.
It's the work of KungKobra, and it's only the most recent record he's set since last time we checked in. Since December he's been breaking his own record fairly regularly, and he reckons there's still room to improve the Any% run.
If you're baffled by the techniques employed above (and you probably will be unless you're a New Vegas speedrunner), KungKobra's documentation is worth a read. All that quicksaving and quickloading is tricking the game into ignoring fall damage and skipping NPC dialogue (among other things), while his fast movement speed is actually a trick tied to leg damage.
"I glitched my movement speed by loading a save at the exact moment my legs got crippled," KungKobra explains. "This causes the game to add the slow crippled speed (roughly 52%) on top of the regular (100%) speed, allowing me to walk at an accelerated pace. This trick is difficult and inconsistent, so I will most likely restart my runs trying to get the glitch."