Olaf

Olaf is a snowman.

History
Olaf was one of the objects that Bart released on to Homer after he did the Ice Bucket challenge.

Olaf appears in a dream Krusty the Clown had. Olaf then turns into his father, Hyman Krustofsky.

Behind the Laughter
Olaf is a character from the 2013 film Frozen.

In the couch gag from "I Won't Be Home for Christmas" Homer appears as Olaf.