So, I booted up Cave Story yesterday on my DSi, and lo and behold, the protagonist is wearing a Santa Claus Hat! Not a big deal, but kind of neat. I assume thet game is designed to do this when the system clock's date is 12/25.

This reminded me of a few other games that did stuff like this. After the Saturn came out (which is the first console I remember having an internal clock) Sega did this with a few games. If I remember correctly Clockwork Knight (can't remember if it's 1 or 2) had special holiday-themed title screens when the system clock was set to the appropriate date.

Ready 2 Rumble Boxing on the Dreamcast had some fun surprises too. I remember the audience consisting of skeletons on Halloween, for example.

In a non-holiday, but similar example, I remember Eternal Darkness on the Gamecube going seriously ape shit if you played the game around midnight.

Is anybody aware of any other games that have easter eggs like this? I posted this in the Modern Gaming forum because this is sort of a phenomenon exclusive to newer machines with system clocks.

Oh, and Happy Holidays, ya'll!