I finally bit the bullet and spent some time this week auditioning new mail clients. Since moving off OS X I have been using
Thunderbird but never quite got to love it. It is not offensive, in fact it is pretty good, but it seemed slow, in a personal opinion, completely subjective manner. So I tried out
Evolution which has been installed on all my Linux desktops because I have been using
Ubuntu exclusively for the desktop since jumping to Linux full time. I had tried Evolution years ago and didn't like it much then because I have an aversion to integrated everything and the kitchen sink type software which I think is the antithesis of the
Unix philosophy. I just want small robust tools, with an appropriate default feature set, that can be extended either through plug-ins or through connecting to other small tools.
This search lead me to
Claws Mail, a spin off project from the Sylpheed mail client, which is small, fast and feature rich. It is easily extensible through plugins and can be scripted, using filters and processing rules, to work with the full complement of Linux shell tools to do significant processing of email. The only hitch in the giddy up was that I couldn't easily incorporate my existing S/MIME certificates into Claws Mail, it does support them but the process is not currently straightforward. It was easier to just bite the bullet and create a new GPG key pair for my email account so that I can let my recipients ensure that the email that I sent is the email that has arrived because in these days of phorm we can't be too careful.
I should also mention
OfflineIMAP, another tool I found whilst exploring the mail client ecosystem. It makes a local offline copy of your IMAP folders so that you can make an easy backup of your IMAP stored email.