I'm just curious, but in Lion's Mail there is a TLS Certificate available in the accounts pane in its preferences. Now, I know this is for encrypting mail. There seems to be an included certificate in the form com.apple.idms.appleid.prd.<hash> Where <hash> looks like some form of UUID. Anyway, I'm wondering what kind of suitability this certificate has for personal use, and if I have multiple e-mail accounts, is it a good idea to use this certificate to start securing them all? Is it personally identifying, i.e - if someone received encrypted messages from e-mail address A and e-mail address B, both signed with the same certificate, can they tell that these two addresses are the same person? I think that for e-mail to really become trusted again technologies like encryption and signing really do need to take off properly, so I'd like to start using them, but I have quite a few different e-mail accounts for different purposes, as I don't want to have to buy certificates for them all. Anyway, I suppose I'm interested in a general sense about how people are using TLS certificates in Mail?