The goose that follows them through most of "End Love." According to The Other Wiki, the goose's name is Maria (despite being a male goose) and while initially hostile through most of filming, adopted them towards the end.
The story of the creation of the "WTF?" video appropriately begins pretty strangely. Mainly, that bassist Tim was in the parking lot of a Pinkberry (frozen yogurt shop) and almost got run over by their friend (also named Tim), which eventually led to the creation of the video.
Most of the outtakes of "White Knuckles", but especially one where one of the dogs knocks over the pail it's supposed to put its paws on, so it tries again with another one.
The very end of the "Needing/Getting" video has the car unceremoniously sideswipe part of the set, at which point one of the guys calls "Did we get it?"