It was Chris Hülsbeck's To be on Top - arguably the first tune to use a fourth voice for digi-drums. Chris often stated that he was officially beaten by Martin Galway simply becouse Game Over hit the shelves before To be on Top. Tough one to prove but there you go.
I think Arkanoid was first. At least before Game Over. (I don´t have a clue if Hülsbeck was first though.) If you listen to the quality of the samples then you hear that Game Over is better and I think I´ve read that Arkanoid was his first project with sampling. But I´m not really sure.