Sometimes, people have life problems that can be entirely solved by doing one thing. (doing X made my life 0.1% better, PERMANENTLY!) These are not things like "This TAP made me exercise more frequently", but rather like "moving my scale into my doorway made me weigh myself more, causing me to exercise more frequently" - a one-shot solution that makes a reasonable amount of progress in solving a problem.
I've found that I've had a couple of life problems that I couldn't solve because I didn't know what the solution was, not because it was hard to solve - once I thought of the solution, implementation was not that difficult. I'm looking to collect various one-shot solutions to problems to expand my solution space, as well as potentially find solutions to problems that I didn't realize I had.
Please only put one problem-solution pair per answer.
Problem:
Regularly eating unhealthy snacks/food.
One-time solution:
Put all the unhealthy snacks/food in a hard to reach shelf in the pantry, and shove them all the way to the back.
Notes:
This solution is very effective in reducing the snacking and junk-food eating. It's based on two laws of behaviour change∗.
Bonus point — A similar trick is actually well-known in retail: whatever product you put in the top shelf (waist-height) near the cashier will sell much more than any product you put in the bottom shelf (even if the bottom product is a much better-known brand).
* These laws come from the book Atomic Habits, which I've read twice and have grokked fully. As a result, I was able to easily come up with dozens of these one-time solutions for all my daily problems. I consider it a life-changing book and I highly recommend it (and I'd love to chat with anyone about habit design, just PM me).