Daily eDeal's Free Email Guide - http://www.dailyedeals.com/connect/email.htm
Provides a comparison of 19 free email hosting sites. All are web based and offers facts and opinions on each one.
Epinions.com: Yahoo! Mail - http://www.epinions.com/cmsw-EmailChat-All-Yahoo_Yahoo__Mail/_redir_att__~1
Opinion and review site that is focused on Yahoo Mail. Provides user reviews on the web based email service.
Free Email Guide - http://www.freemailguide.com/
A guide that looks at many different free email hosting sites. Also lists POP3/IMAP email service providers as well.