email clients
Tollef Fog Heen blogged about that, too. I don't use Gnus (lisp is too much of a mystery to me, and I don't intend on changing that just yet) or Mozilla Thunderbird (I try to avoid anything with Mozilla in the name, except for the browser which is fairly good); but I have to agree on his remarks regarding mutt.
My workaround: ditch IMAP, use Maildir over NFS instead. Works like a charm, hell of a lot faster. That only leaves the folder issue. I've been meaning to write some better-than-biff for a while, which would read out Maildir folders and show some statistics about every folder, possibly with the ability to open mutt on that folder with a single click. Just didn't happen yet...