A phrase used in response to someone starting a new thread/conversation/tweet/etc... about a topic/website/video/etc... that was discussed ad nauseum by the rest of the civilized world a number of months/years ago.

The phrase is derived from the Back to the Future trilogy of movies which involved a DeLorean that could travel through time. The plot of the first movie in the trilogy revolves around the main character becoming trapped in the past when he can't refuel the DeLorean.
Moron: The Cake Is A Lie!

Reply: Welcome to two years ago... Don't forget to refuel your DeLorean.
by Etragorn December 24, 2009
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