Squid and .NET interoperability

I'm new to Squid and finding the granularity with which I can configure it
impressive. But I still have some 'can I do this' questions.

-- interoperability with .NET ? can I trigger events on a .NET app server from
Squid? I suppose if I tried I could compile in some kind of function that would
pass a variable to my .NET box whenever squid logged a hit (or maybe I could
just log to the .NET server and act on the log file ?) What I am trying to do
is use Squid in conjunction with MS ISA Server. The idea is that when Squid
processes a request, it passes the same request to ISA and they double-team the
caching task (there is a reason for this).

-- compression ? I think I will need Apache here. As far as I know, it's
possible, but not sure how to configure this. I assume the non-compressed
content will be stored in cache ? then Apache will handle the compression as it
serves it ?