Have exit surveys vanished?

Since Microsoft introduced Service Pack 2 it has become virtually impossible for web editors like me to find out what users think of our site - at the very moment they leave it.

Yes, I am talking about the good old popup exit survey.

I know that it is possible to conduct a survey via DHTML in a layered window during a user session. But what if I want specifically to do it at the end of a session? Any ideas?

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