For a long time, I've had the urge to move my email processing to Emacs. That would make Email one more function that I wouldn't have to leave Emacs to handle. I have found three candidate packages for this: mew, mu4e, and gnus.
Most everyone agrees that
gnus is the 800 pound gorilla but that it is difficult to learn. Now Chen Bin has published an interesting post entitled Practical guide to use Gnus with Gmail. Even if you're not using Gmail, the guide is still useful. The main differences are in configuration.
I like that he takes the tack of “here is the 5% of
gnus that you need to get started and manage your day-to-day email chores.” That's especially nice because
gnus is built-in and all you need do is configure it to try it out. Of course, that configuration is far from trivial but Bin shows what you need to do to get going with Gmail. If you're using another service, the EmacsWiki shows you how to configure POP or IMAP.
After covering configuration, Bin demonstrates how to read, send, reply to, and search your emails. If you've been thinking about trying out
gnus or, like me, looking for a way to handle email from within Emacs, you should take a look at Bin's post, especially if you're using Gmail.