Nethack, Elite, Captive, Elder Scrolls, Magic Carpet, Simcity 2000 (reticulating splines)... oh, and a little game called Minecraft.
Procedural generation is common. The way Dwarf Fortress does it where the rules and game elements change is nearly unique. Pretty much just that and Nethack, AFAIK, which is why Dwarf Fortress stuck with Nethack-style ASCII so long.
Somebody's using the Magna Carta backwards again...