Pencil Test is also an animated short from Apple Computer in 1988.
In 1988, Apple was eager to show off the graphics power of its Macintosh II line of computers. Using a program called Super3D, a group of talented artists produced Pencil Test an animated short created entirely on the Macintosh. Keep in mind that QuickTime did not exist in 1988; the movie was output frame by frame to an imagesetter, and then recorded to film.
The plot is this : There's a classic Macintosh running MacPaint. The pencil tool jumps off of the pallet and onto the real world desktop (becoming colorized in the process). The pencil then has some adventures on the desktop, and then more trying to get back onto the screen.

It can be seen at http://www.uriah.com/apple-qt/pencil-test.html