The Virginia Journal of Law & Technology has published an article about wardriving: I confess that I haven't had the chance to read the whole piece, but the author concludes that wardriving is legal and that hackers are informally developing an ethical code that demarcates between essentially identifying hotspots and stealing information transmitted over the networks. The article cites some historical court cases surrounding wardrivers and looks at the positive changes in vendor security standards that wardrivers have affected.