There are times when it's necessary to do rather complex queries
in an ASP page. While you can warn a user that a request might
take a while, that doesn't always stop them from clicking on it
and then not waiting to get the results.
Before starting that next call to your DB for the even more data
you've just decided you're going to need, you might want to just
pop your head up and check to see if the user still cares about
By default, ASP scripts continue to run to completion even if the
user has left. By checking the Response.IsClientConnected propery,
you can check to be sure the user still wants the result before
embarking on that CPU-killing query you need to run to get it.
Microsoft has a nice simple "How To" on the topic in their
Knowledge Base: Q182892.