Dunno if anybody here cares about flash games, but I had a lot of fun with it (rediscovering it after remembering having played it like two years ago).
there's two versions,
http://files.filefront.com/combatheavenswf/;9299929;/fileinfo.html being the latest (has save/load!), but requiring download rather than just playing in your browser window
Should I explain bits or would you rather find out for yourself?
Oh, but I guess I should at least introduce it. 2D shoot 'em up with enemies pouring in until you reach some objective, "boost" dash ability lets you cover ground quickly (and fluidly, feels good man) by doubletapping left/right (or z/c), has buyable weapons of varying usefulness, 3 armors that all behave somewhat differently from the others... fast, uncomplicated shooting mostly.