I don't have a link as it was an internal project but it was a simple ASP.NET MVC app that interfaced with Yubikey (a 2 factor dongle) and Active Directory. It

I don't have a link as it was an internal project but it was a simple ASP.NET MVC app that interfaced with Yubikey (a 2 factor dongle) and Active Directory. It would set the Yubikey password to the Active Directory for a user which would then be used to authenticate users when they logged into the network. It wasn't much work but saved the company about $20k, which was the cost of the commercial version the company was looking into.