unroll.me
Unroll.me is a free service that will clean up your e-mail inbox, unsubscribe you from everything you don’t want to receive, and get all the newsletters, listservs, and e-mails you want rolled into one daily digest. A hundred e-mails are turned into one e-mail. Your inbox has never been happier. [sourse-ADDITUDE]
(unroll.me; Gmail, Google Apps, Yahoo! Mail, Outlook.com, AOL Mail, iCloud; free)