The vehicle in which Mermaid Man and Barnacle Boy drive in the Nick show, Spongebob SquarePants.
Barnacle Boy: Aw, tarter sauce. Where did we park the invisible boat mobile?
Mermaid Man: Right over here, I though...
Barnacle Boy: Nope, I can't find- *BAM* ...found it.
Mermaid Man: You walked into it again, didn't you?
Barnacle Boy: *grumble.*