As our site has gotten more high profile, the number of times we are finding password trading has occured is increasing. We are beefing up security again, but are also concerned about the impact this might have on our members. How are yall dealing with this problem? We added a filter that is blocking out all sites that are know trading sites (as we find them from the referring url list) as well as limiting concurent log ins..What else is good?

thanks
Alex