Playing Akkanvader -- known as "Space Invaders '95: Attack of the Lunar Loonies" in the West -- from the Taito Memories: Last Volume (aka Taito Memories Gekan) collection on PS2.
A highly animated, cute-em-up take on Taito's own Space Invaders, Akkanvader is colorfully wacky and actually plays well--and not too flashy on the retinas (the bosses flash a little when you hit them).
Up to the point I'm capable of reaching currently, it's all good fun. Looking at plays by people who actually know what they're doing, I worry a little that it turns into the usual Space Invaders race to stop the ships from reaching the bottom of the screen, which to me was never very fun. That, however, would be in the future. ; )