After reading Jan Tielen's blog entries Integrating SharePoint 2007 and jQuery Part One and Part Two I wrote a simple SharePoint solution on Visual Studio 2008 that installs jQuery scripts to SharePoint.
One nice day I discovered that MOSS2007 search site didn't work anymore on test server. Well, the only thing that worked was indexing on file system level. But SharePoint content indexing was out of order. I found some information from web about this issue. Specially helpful may be blog entry Access denied when crawling MOSS Content by Sven Gillis. But it was only part of solution.
In one of my projects I had to read data from Exchange Server 2003 programmatically. I had access to Outlook Web Access that used Form Based Authentication (FBA). After some hacking and testing I got authentication part of my utility work. The point was easy - before making WebDAV requests to Exchange Server we need authentication cookies, so there is active session we can use.