SigPro (was SignatureProfiler) is a plugin for Apple's Mail application that adds missing features from the way that signatures are handled and managed with your outgoing mail messages, especially if you have multiple mail accounts (and who doesn't these days). It was originally written to make up for the complete lack of signature management in versions 1.x of the program, but even 2.x is still missing some capabilities if you use several different accounts and want to share signatures between accounts.

Mail Detective tries to determine the geographical origin of email messages in your INBOX via geolocation by parsing the message headers for the sender's IP address, which makes it easier for you to check how plausible the message is. Simply drag the email from your mail program and drop it onto the app’s window - Mail Detective will tell you the country and, if this information is available, the city from which the email was sent.