Very cool! The GameBoy camera is an interesting piece of hardware. If you're serious about finding the origin of these photos, you might want to spread it around some Japanese forums - the UI of the first few pictures is in Japanese (ニンテンドー is Nintendo and ポケットカメラ is Pocket Camera). Plus, the V hand sign you mention is a common hand sign in Japan. Good luck!
Wicked cool! Now I'm digging around my apartment trying to find my GB Camera!
In addition to photos, the Gameboy Camera has a music sequencer thingy. It would be cool to be able to download the music you make from a camera.
I had forgotten how horrible the resolution was on that camera!
It also only has 4 colors - white, black, light gray and dark gray. This is a limitation of the gameboy display, although the photos look like they are dithered. It would be interesting to know what kind of quality the actual camera sensor has.
A strange coincidence that I was actually just reading about the CMOS sensor in the camera yesterday. You can see yourself the quality of the sensor here: