Rymoka's youtube channel has a lot of those old toonami promos, they're all great. Melancholic nostalgia for when you're lying in bed awake at 3am wondering where your left turned left.

As for me, I don't have any particular comfort movies, but I do rewatch old anime from time to time when I'm feeling down. Kenshin, Cowboy Bebop, Trigun, FMA, Outlaw Star, Champloo. Whatever matches my mood. Or I'll replay old video games for comfort. Maybe speedrun SotN for the 1000th time, or replay the entirety of Wild Arms or LUNAR. Maybe hop on to ol' Destiny 1 and do some 10-minute strikes, Dragon's Dogma to take down the online dragon with Maker's arrows, or emulate River City Ransom (or the RCR-inspired PS3/360 Scott Pilgrim game) to beat up on some fools. Maybe Warframe.

The problem I seem to have is that there are too many options that are close to comfort but not really comfort. It always feels like there's something better I could be doing/watching/playing.