Well if you look at it at this way, sampers now a days are atracted to RP (Lame) so making some decent script for RP mode will have it's raputation, E.G:An email system based on dialogs maybe?
To add on to that: Use MYSQL and send messages to their real email, or make a full email system. Like people register emails..etc. That would be cool, but it's easy to say and won't be easy to script.