Propcorn

Social challenge site (especially when followed by the words "dot" and "com") where people can legitimate prove that they "knew" that one thing all along...
I knew Casey Anthony was going to be let off the hook. I chose "no" on propcorn.com......

or something that looks like this: propcorn.com/prop/265/will-the-urban-dictionary-definition-of-propcorn-have-more-up-votes-than-down-votes-by-72611/
by DrRickDaglessMD July 05, 2011
Get the Propcorn mug.

propcorn

Fake popcorn used as a prop.
"Ah, thank god. Some food."
PTOO!
"Eeewww. This is propcorn."
by Rocko Starr September 10, 2009
Get the propcorn mug.