Well, all threads you've read appear as read. And at the bottom of the mainscreen you can click 'mark all topics read'. So if you do that every time before you leave, you can see which posts are new the next time.
We used to have a link to the chat at the front page, but it didn't really make a difference. I suppose we could bring it back, seeing how it doesn't take more than a few lines, but don't expect it to generate more traffic.
Thanks for responding, but this isn't the same thing. If possible, I'd like to be able to hit a link and it would show a list of all topics I haven't read. You'd have more people reading more topics this way as they'd be visiting the site more often.