Google has a serial-killer-grade stash of knowledge about its users. This is not news, but to really ram the point home, Google is releasing a tool that lets you go back through history, and retroactively follow your every move.
The Timeline feature is rolling out slowly for Google users on Android and desktop. If you've got Location History turned on (it is by default, but that's easy to change in Google's privacy hub), you can open Maps, and view your "real-time routines" — i.e. voyeuristically stalk yourself like there's no tomorrow. Just click the side menu on Android, or options button in the search bar on desktop, and 'your timeline' is innocently hanging out under 'my places'.
Google frames the option as a way to remember the bar you stumbled across the other day, and all slightly-too-close-to-home jokes about Google's creepiness aside, I can actually see the uses for Timeline: recalling what you did whilst blackout drunk will be easier, for a start.
There's also a few other integrations built in: if you use Google Photos to save geotagged pictures, they will show up alongside your location trace, for extra nostalgia points. You can also click on spots you frequently visit and give them names, which translates over to regular Google Maps and Now usage.
This is also probably a good time to remind you that Google has a two-factor authentication login option, and if you weren't using it before, you sure as hell should be now.