I really enjoy the power of mutt, and I've to say that I've not too far from reaching the email Nirvana with it :). OK, it's not the email client for everybody, it's just for the people that prefer the keyboard to the mouse and love the command line interfaces.
There's only one missing feature in mutt: a nice way to notifiy new emails. The problem with mutt is that I need to periodically switch to the mutt shell to check for new emails. And I don't even like the crappy notification balloons that cover the useful part of the desktop (e.g., thunderbird). A small tray icon could be a solution (and I did it this way for a while, patching mutt), but with the icon I don't see immediately the message that I receive.
This led me to notice a large unused area in the gnome panel at the top (recently I moved from Fluxbox to Gnome, yeah! :) now I've a ultra-very-fast SSD I can also use a fancy desktop environment). So, why not to use the top panel to notify the subject of the last email I received in my mailbox? ta-da! the solution: a small python gnome applet that periodically fetches the last unread email from a generic IMAPS folder in gmail and prints the subject to the panel.
Here's the code: gmail-check, very minimalist and designed just for my particular desktop environment, so it may not work in some cases...