I think I have quite a lot of stuff still to see of which I don't know the results yet, probably I'd just end up watching that (two years worth of MMA mainly)
If watching some replays of multi-sports events, for me it'd be about Olympics, probably 2012 or 2008 - Olympics that I have actually watched, but aren't so close anymore to still remember most things. A more useful/normal time of life is about to start though (you know, work and such), so I'm probably not gonna have a whole lot of time to spend 1-2 hours a day watching things I've already seen