I started using my first computer when my father bought me and my brother a ZX81. Thanks dad - that computer somehow brought me to where I am today.
We moved on to a Commodore 64 along the road. And a game that made me and my brother incredibly popular with all the boys on the road and which somehow still has influence on what games I play on my PC was M.U.L.E. Game. It was a turn-based game where up to four players took turns developing resources on an alien planet. It was great fun.
I just found a web site that has some information on M.U.L.E., it allows you to hear the title soundtrack, and then it apparently lets you download the game too. I haven't tried out the download yet, but I certainly will do.
The site that I found was Atari MULE Online.