"Mozilla Thunderbird is the safe, fast email client that's easy to use. It has lots of great features including quick message search, customizable views, support for IMAP/POP, RSS support and more. Plus, the portable version leaves no personal information behind on the machine you run it on, so you can take your email and adress book with you wherever you go."
You can manage multiple email accounts.
Gmail POP3 and IMAP compatible email client.
