We have used 1 CLR total. It simply looks up user data in our AD for some custom permission stuff.

That being said, I'm moving to a new home/project/environment. It may very well require the use of CLR. This is an analytical environment that currently sits in MySQL, but there is a desire to investigate SQL2008 for performance and scalability... SQL2005 wasn't an option because time didn't resolve finely enough. It is the largest db I've ever encountered.

This is going to be very interesting.