Setlist.fm

This is one of the few things the internet has given us that I think is unequivocally good and can be SO USEFUL!

For live concerts, this site tells you what the artist you’re seeing has played in previous set lists (hence the name), but also it usually lists when they actually took the stage (and when the opening acts did). It gives you little trivia bits like, “oh, it’s the first time they’ve played this song live in 10 years.” If they bring out a special guest onstage to perform and you have no idea who it was, this site will tell you.

They track concerts going back decades — it’s not perfect, because it’s users providing the data, but if you ever wanted to harness the passion of fellow music nerds connected via 1s and 0s to help you figure out how late you can be to a show and not miss too much… this is an indispensable tool!