From Synthetic Picturehaus -- the filmmakers behind last year's delightful mockumentary "Aperture: A Triumph of Science" -- comes a new Portal fan film: Aperture: Lab Ratt.

Lab Ratt tells the story of everyone's favorite wall-scrawling former Aperture Science employee, Doug Rattman, and will also feature Chell, GLaDOS and other familiar Portal characters.

Although it's only a (very impressive) trailer thus far, Synthetic is seeking funding to make Lab Ratt into a complete short film.

[thanks, melissa!]