We use a custom DLL to display Claims in SharePoint in a webpart. It is very handy but when we moved from 2008 to 2012 server we ran in to a small problem. We would normally just drag and drop our dll into the assembly folder in windows 2008. In 2012 it is not so simple. Luckily I found this great post at http://camerondwyer.wordpress.com/2013/05/22/how-to-install-a-dll-to-the-gac-on-windows-2012-using-only-powershell-without-having-to-install-sdk-or-visual-studio/ and it saved me a ton of time and having to install VS or a development toolkit on the server. Thanks Cameron Dwyer for posting and making my day go a lot smoother.