Don't show your email address in your user profile. Go to your profile "Settings" and check the box "Hide email address". Also, if you use a hotmail email address as your contact address, be sure you sign in to your hotmail account once a week, otherwise your account will expire and another user can register it. To see your profile, go to http://profiles.camfrog.com/nickname
where "nickname" is your Camfrog nickname.