Preeeeow
From Homestar Runner Wiki
Preeow is an ontomatopoeia used to describe The Paper's sound effect. Saying it often signals the end of an email, and characters use it as a verbal cue for The Paper to come do his thing. Strong Bad first made use of it in autobiography, and it has reappeared a couple of times since, occasionally used by different characters.
It also appeared on a note taped to Mrs. Benedetto in part-time job, offering Strong Bad's "official" spelling of the word: Preeeeow. However, it is often shortened to two e's for easier use on the Wiki.
