Which email client do you use?

[Zoidberg]

I've tried virtually every email client since the days of Claris Em@iler and QuickMail, and I always come back to Apple's own Mail.app since the beginnings of OS X.

Some add-ons from SmallCubed (notably the simpler filing options and the ability to set when a message is sent) make it pretty perfect for me.

The only client I really gave serious time to was Unibox -- I liked the sort-by-sender layout -- but it's long since become abandonware.