http://en.wikipedia.org/wiki/Midwinter_%28video_game%29
Was talking to my mate about early copy protection that demanded that you enter info from the manual or a paper disk or something before a game would let you play and this game popped into my head.
The press went wild over it at the time and it was pretty cool. It was actually the sequel that I played but I think they were pretty similar. The game world was a big blocky polygon landscape that you were free to roam and collect missions sandbox style. I spent hours on it.
Anybody else remember playing it? Funny how some games just get forgotten about.