Scratch Meme

A Scratch-Meme is a series of remixed versions of a particular subject, usually Character-Making.

Tokis (on Bucket Crew Wiki)
Tokis are a very famous meme, started by Maki-Tak. Her widely-used reptiles soon became a favourite, amongst various spin-offs.

Hamsters
Doody's character of the same name are very common amongst younger audiences. They're noticed for frequent flame-wars with "Doody-Haters "

Anthros/Furries
Anthros are anthropomorphic (hence the name) wolves, cats and other furry creatures created by users, usually to roleplay. See more info in this Wikipedia article.

And last but not least...

Caramell Dansen!
Caramell Dansen is a popular internet meme. It consists of the same annoying song over and over with a really strange dance.