This post falls under the "I don't want to forget this and have to find it again" category. When you're working with WCF and need a self-signed certificate for authentication it is not always easy to find the right article to figure out how to do it. This is the command that I use…

makecert.exe -r -n "CN=MyService" -a sha1 -eku 1.3.6.1.5.5.7.3.1 -ss my -sr localmachine -sky exchange -sp "Microsoft RSA SChannel Cryptographic Provider" -sy 12 –pe

You can use this to generate a certificate to use as the service credentials when using UserNameToken to secure your messages.