i.Scribe

Scribe is a small portable email client with an integrated contact database and calendar.

It supports all major internet mail protocols and uses international standards whenever possible. Scribe does not require to be installed or uninstalled and can be used from a removable drive without reconfiguration. It comes with a Bayesian spam filter and translation into many different languages. Updates are posted regularly to respond to issues and add features. Since Scribe works on Windows and Mac, you can take your mail with you whenever you change the operating system. And don't worry about viruses, Scribe protects you from the usual vulnerabilities in other email clients with its own virus-proof HTML check and executable attachment protection.