When you are developing .NET applications for your business you will need to deploy these to production at some point. Usually you will deploy the tool to a network fileserver and let the users run the application from there without local installation.
Of course one can use click-once since .NET 2.0, but sometimes the company developing the software will charge you a fortune for some minor changes like this (or digitally signing the application).

Well, I found another interesting way to configure the .NET security policies and deploy these via an .MSI installer file or even via a GPO (group policy object). Hence you can combine granting access rights to the file share with the deployment of the GPO. Nice.

Also, there are some really good Security Policy Best Practices at the MSDN site.