This glitch can be pulled off if you have a fishing rod!
Step 1: go to post office(don't go inside!)
Step 2: run towards from the east side to west side until you get to the window and press A button.
This may take a while because its a little hard to do. Once you get the hang of it, you'll be able to pull this glitch off!
The bobber will roll off the roof of the post office. This will not corrupt your game in any way. It's just a funny glitch!
This can also be perfomed on Nookingtons!