Repositories are awesome, and we should have more of them.
I recently completed BJ Fogg's Tiny Habits, and it's a pretty lightweight way to install new habits (recommended). However, I realized I could use a better repository of useful habits.
So, please use this thread to suggest habits that you've found useful. Bonus points for evidence/anecdata of usefulness.
Obviously, 1 habit per comment makes upvotes a clearer signal of collective approval.
I am always amazed that everyone doesn't assign a pocket to things. It's something I'd honed as far back as middleschool after repeatedly loosing my camera due to a messenger bag without a zipper and a tendency to set things down less than carefully.