My vote goes to Rodekill: A day in the life. I still sing "tiny bubbles" sometimes. 
But for a professional game I like Space Quest 3. I think that games' soundtrack sticks with me because it was the first game I heard on a soundblaster.

But for a professional game I like Space Quest 3. I think that games' soundtrack sticks with me because it was the first game I heard on a soundblaster.