At one time I used a CLR string aggregator (catenate with commas between) with code taken from the SQL Server developer samples, and for a while I used an open source CLR geospatial extension (can't remember what it did). I never developed SQL Server CLR code from scratch.

These uses were not terribly important, but when I tried moving a subset of the database to SQL Azure (using the limited usage that came with my MSDN Premium subscription), I couldn't do it because of those extra assemblies. All I was doing was experimenting to become more familiar with cloud services, but I ended up concluding that, at least at that time CLR and cloud did not mix.