Note: this entry has moved.
Turns out, you cannot give it a quick try unless you start changing your site's pages to include a piece of script before the </body>... yuck!
I searched the web and found no one who had done the simplest possible thing to have transparent support for Google Analytics on your site without touching a single page: a custom IHttpModule that uses the HttpResponse.Filter property to detect </body> and add the script automatically before sending the buffered output.
If your site is not a high-traffic, performance-sensitive one (i.e. your corporate site/blog/small community site), you may find this little guy useful (note that I only had about 20' to get it working ;-)). Download the module for .NET v.2.0 or the one for .NET 1.1. Configuration is mininal:
<add key="GoogleAnalyticsAccount" value="[Google Analytics Account #]"/>
<add name="GoogleAnalytics" type="Clarius.GoogleAnalyticsModule"/>