According to this review of the Samsung BD-P1000 BluRay player, the initial batch of BluRay titles from Sony come with a hidden easter egg: HD test patterns:

Videophiles and professional calibrators will appreciate an "Easter egg" that Sony has added to the initial Blu-ray movies I've seen so far. At a movie's main menu, key in the number 7669 and a series of HD test patterns begins to play. The selection of test imagery includes color bars, a resolution-test pattern, a grayscale ramp, and other screens that can be used to optimize the picture quality of a connected display.

Since no one from the BluRay camp has provided us with an evaluation BluRay player (hey, we'll spring for the software if you provide the player!), we can't verify this report. If you're from Samsung and you're reading this, please contact us to make the necessary arrangements.