....Ok maybe not the best game ever.. but definitely one of the best classic style hidden Mini-Games I have ever played. I may be a little late on this but I just stumbled upon this myself and was blown away enough that I felt should let some of you know about this gem who might not know about it already.

Basically it's hidden inside Project Gotham City Racing 2. How do you get it? Simple. You just start up a game, go to the "garage" in the startup menu, press Y to go to walking mode, then go to the arcade cab! It's that easy.

It's a cross of Robotron/Smash Tv style gameplay with Tempest-like color vector graphics. And it's fast! Fast and fun. The longer you survive, the better your weaponry gets - faster bullets, a wider spread, a certain amount of homing ability -If it had a few more enemies, I think it would have been good enough to stand on it's own and be a hit back in the day.

Check it out.. to me it's like you get PGR2 for geometry wars and consider the driving game a small extra

more info here: http://worldofstuart.excellentcontent.com/geowars.htm