If you've got a cardboard stash you don't know what to do with, take a cue from this gallery and put it to good use -- by pranking others!
STOMPer RilaK says:
"If you've got tons of unwanted cardboard and time to spare, why not have some fun before throwing them out!
"Pick a victim, then spend an afternoon covering his furniture and belongings with cardboard.
"He won't know what hit him."