How about an option to put an indicator on classified and forum pages when there's something new that the member hasn't seen? Sort of like on an iPhone where an app gets a red circle with the number of unseen items in it. You'd have to know the last time the member opened that page and I'm not sure if you track that currently. Or I guess you could leave off the count and just put an indicator if something new was posted since the last time the member loaded that page, which would be slightly easier.