Its kind of short but every time I get sad I load up this clip of Northernlion messing around with spray paint. It never fails to get a smile out of me. I have probably seen it a billion times.

The other one is the opening trailer to Final Fantasy 14: Endwalker. I cannot put into words how life changing that game was for me and quite a few people I know. I would avoid watching the trailer as its kind of loaded with spoilers but at the same time you have zero context. I think I watched this thing on loop for 3-4 days straight.