Anyone who isn't familiar with this guy yet, allow me to be the one to indoctrinate you, because this guy's stuff is pretty amazing in my opinion. He started this just as a hobby to share with friends and family, but it has quickly blossomed into a huge following just in the past 2 months. He takes music themes from (at least thus far) several beloved classic games, painstakingly picks apart each 'track' and isolates it start to finish. Then with the help of a metronome, he records each track purely acapella, and then combines them into a master track and posts a multi-panel video of the results. Thus far a good chunk of the work he's done originates from Zelda or Final Fantasy games, but he's got some other stuff in there. I'll follow up with a few posts of some of my favorites after this initial post.
Side note: if you watch the video panels carefully, he often 'features' his cat in one of them, which is usually pretty funny.