— David Weinberger
Nothing has ever been said just once. (By the way, there are no google hits on that phrase.)
The above quote was dug up while trying to find the origin of another quote:
On the web, everyone is famous to 15 people.
Apparently, noone knows exactly who said that one first:
— Andy Was Right, TIME (from the future!)
Appropriately enough, many people share authorship of that one.