The little dot that shows that a user is online is a great feature. I just responded to a question from a user who was flagged as online. I thought it would be a nice feature that if a user is online when someone posts to his/her thread that there could be some visual feedback to that user that there is a new post. Not being a web programmer (and having no desire whatsoever to learn) I don't know what kind of feedback could be used. Private messages are flagged by changing the colour of Private Message at the top of the page. Perhaps something similar like changing the colour of the Username to the left of Private Messages.