Do the Mario!

From Mario Fan Games Galaxy Wiki

When Mario Fan Games Galaxy's forums were on the EZBoard system, Cyberknight Aaron created a topic with the Super Mario Bros. 1 overworld theme embedded. The topic was titled "Do the Mario" and was based off of an ending of the same name from the Super Mario Bros. Super Show.

Eventually, more or less everyone on the board was participating in the events of the topic. It eventually reached 100 posts and was locked; after which the topic was moved to the Vault and left there. It is considered to be one of MFGG's first fads.