Very cool, what game system are you using?
The Dark Future from GW (1988). They did give the rule-set a time ago on Specialist Games but they have disappeared from their site. Even had a supplement called "White Line Fever". Here you have a PDF of the basic rules : http://www.games-workshop.com/MEDIA_CustomProductCatalog/m1340008_Dark_Future.pdfYou can check further here :http://boardgamegeek.com/thread/251079/well-its-back-rules-are-up-on-gw-site
These look awesome