GMail
We personally use and recommend GMail, the free email service from Google. Gmail provides nearly 7500 Megabytes of free email storage and they allow you to use POP3 and SMTP. Their spam filter works very well, keeping out most of the spam. We also appreciate very much their extremely fast search capability, which makes it very easy to search your archived emails.

Yahoo Mail
Yahoo provides a free email service. POP3 and forwarding, however, are premium services requiring an annual fee.

MyRealBox Free Email
The folks at Novell provide the MyRealBox service as a testbed for their Novell NetMail email product. There are occasional service interruptions, but in our experience, it has been an excellent service. One of the best features is that you can use POP3 to download your email. Because MyRealBox is a test bed for Novell NetMail, they are not always accepting new accounts, so you may need to check back periodically.

Mail.com Email Service
Mail.com will provide you with a free email address. They used to provide free forwarding but now it is considered a premium service with an annual fee. You can read and send email using their web interface, but they seem to have a lot of pop-up windows with ads.