bored 1 day, I decided to test the theory of, "window post"

you throw something out the window and shout an address, then it goes their and a few days later you get something back through the window in return (I'd been thinking about the possibility for a few days, but I never actually tried it)
so I through a toy out of the window (1 of those plastic toy men you get)

for days I just sat by the window, waiting for my reward

then 1 afternoon something came sailing through the window and landed in my hand

the exact same plastic toy man I through out only a few days ago.

from then on, I believed in window post, and still do today