Pretty much anything from the NES block, Mega Man 1-3 relay race, Awful Games Done Quick block, Bloodborne, Mario World race, Super Dram World and if you played it as a kid Final Fantasy IV / II.
Edit: Zelda: Link to the Past randomized race was awesome.
They raised $2,267,377.96 this year, so about $45k more than the record that was set last year. 108k came from Twitch chat in the form of subscriptions and bits.
It's crazy that about half the total is donated on the last day.