Mu4e is an emacs email client that seems to work pretty swell. It is a bit of a hassle to install. If you want to use it, then you probably need to have a gmail account. If you have a hotmail or a yahoo account, then you will have a harder time using mu4e.
Mu4e does not get your email. It does not send your email. Mu4e is a great tool at searching your email. It's freakishly bizarre at how fast it can scan your email.
Mu4e is so fast, because your email is stored locally in a Maildir. You need to create a local copy of your email. To do this you can use isync or offlineimap. Isync is faster and the developer of offlineimap is creating a new tool that will replace offlineimap. So use isync. Isync is probably the fastest way to create a maildir. It can be a bit of a pain to set up. Google might not let you sync your emails by default. You need to specify that you want gmail to allow "insecure apps" to access your email. grr. Good old compiling it manually.
http://www.djcbsoftware.nl/code/mu/mu4e/index.html#SEC_Contents