Putting the wrong stamp on a letter is a mild frustration, but it can be easily remedied with a microwave. YouTube user Household Hacker reminds us that you can also use it to remove stamps from letters.
Next time you put the wrong stamp on a letter, just pat a few drops of water on the stamp, then nuke it for 20 seconds. To be safe, I tried this on my microwave's lowest power level, and it worked well.
10 Things You Didn't Know Your Microwave Could Do! [HouseholdHacker]