Noun - When in an instance when you need to prove someone wrong, just pull some Wikigraffiti and you'll be safe.
Verb - It is pretty typical of people to Wikigraffiti the "George Washington" page on Wikipedia.
Garth - "Sweet. Let's Wikigraffiti that shit up."
Wayne - "Haha, 'The Battle of The Bulge' is now defined as an era in the 80's when Hair Metal bands would try to stuff their pants the fullest in the crotch region, then gloat about it!"
Garth - "Shwinngg!"