getmail is intended as a simple, secure, and reliable replacement for fetchmail. It retrieves email (either all messages, or only unread messages) from one or more POP3, SPDS, or IMAP4 servers (with or without SSL) for one or more email accounts, and reliably delivers into qmail-style Maildirs, mboxrd files, or through external MDAs (command deliveries) specified on a per-account basis. getmail also has excellent support for domain (multidrop) mailboxes, including delivering messages to different users or destinations based on the envelope recipient address.
OfflineIMAP is a tool to simplify email reading. It allows you to read the same mailbox from multiple computers and ensures that your changes will be automatically reflected on all computers. You can use various mail clients to read a single box or read mail while offline with full synchronization when you reconnect. You can read IMAP mail with readers that lack IMAP support (same goes for SSL). OfflineIMAP's multithreaded synchronization algorithm performs between 10 and 60 times faster than many mail readers' internal IMAP support, and it can be used even with mail readers that support IMAP already. There are five available user interface modules, including scripted execution, an interactive terminal interface, and GUI interfaces.
MIR (mobile IMAP reader) is a WAP frontend for reading email from various IMAP accounts. You can browse and read email messages stored in different IMAP mail folders. It is developed with efficiency in mind, and optimised to present all information on a mobile phone in a compact form without any overhead.
Twisted Mail provides client and server implementations of SMTP, POP3, and IMAP4. These differentiate themselves from the Python standard library implementations both by presenting a much higher-level, easy-to-use interface and in their server components, which allow the implementation of custom servers for each protocol without dealing with protocol-level issues. Twisted Mail includes a simple demonstration email server which accepts messages over SMTP, stores them in a Maildir arrangement, and can serve them to clients over POP3.