Buffer Time Travel

Vim allows you to go to an earlier text state for a buffer with :earlier. For instance, if you want to see the state of the buffer from 10 minutes ago:

:earlier 10m

Similarly, you can move back toward the present text state of the buffer with :later. If 10 minutes earlier was too far, you can come back 5 minutes like so:

:later 5m

I encountered these in Nick Nisi's 'Vim + Tmux' talk.