Hi, I am the author of _Overcome Email Overload_, and I watched a LOT of people use email and interviewed them about their practices. I have distilled what I t

Hi, I am the author of _Overcome Email Overload_, and I watched a LOT of people use email and interviewed them about their practices. I have distilled what I think is needed into http://www.emailoverload.com/philosophy/PerfectClient.php http://www.emailoverload.com/philosophy/PerfectClient.php If you want to check out my book online, see http://emailoverload.com/eudora/html/index.php http://emailoverload.com/eudora/html/index.php for the Eudora 5 version and http://emailoverload.com/outlook/OEO-O.complete.pdf http://emailoverload.com/outlook/OEO-O.complete.pdf for the Outlook 2002 version. (They are very similar, but use different terms and reflect the slightly different features of Eudora and Outlook.) IMHO, the most important part to read is the beginning of Chapter 2. I have also written some email clients. I would agree with dazzawazza that you should not try to write your own POP/SMTP/IMAP code. It is really easy to write a simple POP/SMTP email program, and incredibly difficult to write a good email program. (For example: attachments can be recursively nested, yuck! For example: IMAP clients must be able to accept input from the server at any time.) All the popular languages -- C, C++, Java, Python, Perl, PHP, and undoubtedly Ruby -- have robust email libraries. I wouldn't be surprised if even some of the lesser-known languages like Erlang and Squeak have good libraries as well. I would suggest building on top of Firefox, GMail, SquirrelMail, or Evolution, depending upon what your goals are. You might also think about contributing to the Chandler project. Good luck!