Listening to the RPG podcasts, it seems that a few people have adapted different games to the Shadowrun setting. Mortal Coil and Dread, I believe, were mentioned.
What I want to know is: has anyone run a Shadowrun game with PCs as anything but criminals and freedom fighters? Has anyone run an entirely different style of game in the Shadowrun setting? Did you use the Shadowrun rules, bring in rules from another game, or roll your own?