I use Trello for all kinds of stuff. For example we have a grocery board, so if I'm at the grocery store I can pull it up and make my trip more effective. Every Saturday morning I bang out my weekend todo list in Trello. Whenever my wife and I are going to do just about anything: go on a vacation, buy something, whatever, we make a trello board for it.

Also Google Inbox's reminders were an honest to god game changer for me. I pretty much don't forget anything anymore. I even have a recurring "take out the trash" reminder pop every Sunday for example.