A reference to a penis that's been inside of a lot of people, in the sense that a tour bus goes everywhere - this person's dick has been everywhere

It is not uncommon to hear of an STD-infested Colorado Tour Bus

v. collectively or individually finding someone/something to blame for a problem, as opposed to brainstorming which connotes finding solutions to a problem

n. the act of finding someone/something to blame for a problem

(from a TV ad for HD television)