If you want to follow a particular thread without getting involved with it then you subscribe to it. I've just subscribed to this one, not sure if I will get an e-mail when you get answers though.
Hi Ralph and peanut, just got an e-mail to say there was a new answer posted to this question. Strangely enough though it didn't send me an e-mail when I posted my answer. Maybe a clever bit of programming there by AB.