At my hotmail, I receuved a notification that someone had replied to a thread I subscribed. As I wasn't interested in it anymore, I clicked the link which unsubscribes me for the thread, but something starnge happened:

I clicked, it opened a new window (with the hotmail horizontal frame) saying that I have unsubscribed myself from the thread. It started loading another page, which was the same, but instead of one hotmail frame, it apeared two of them. When I waited again for the new page, a third frame apeard, etc. Always saing that I unsubscribed myself to the thread.

It was the first time I unsubscribed myself to a thread from the email link.