I thought you were joking Randwill. oops
To me Atomic Mutant is a great time killer game that I keep on my hard drive - like Bejeweled - but so much funnier and in it's own deliciously warped way engaging. It's a tribute to all the Sci Fi B Movies from the 50's and 60's.
It's not a shooter - more like a first person very simple arcade type game with lots of unusual charm. It is one of the strangest and most fun diversionary games I have played. You are the giant mutant, you can watch through your eyes or through cinema scope with all the people in the movie theatre or drive in audience. It is pure silly fun.
Didn't intend to make light of your question - I assumed you knew about the game.