my favorite bit of speedrunning tech of all time has to be grab boosting from 2013 flash game bfdia 5b. for context, for a large section of the game, you play as 2 characters (book and match). you can only control one at a time, and have to manually switch between controlling them. grab boosting involves switching to book, grabbing match and throwing her upwards, then quickly switching to match, grabbing book while still in midair and throwing her up too, then switching to book again and repeating the process. the input density needed to gain significant height with this is insanely high, so real-time runs use it relatively sparsely, but the moment the tas for the game gets to the 2-character section it starts completely ignoring the levels in favor of just flying over them in this fucking hillarious routine ripped straight out of those trollface physics comics. go watch a 5b tas i promise its really good