I recently wrote about how I use Evernote as my main tool as a School CIO. It is my primary tool for work, and home. I just did some more with it that I found useful and liberating - emptied my inboxes!
Yes, you heard correctly, my email inboxes are empty. I used to keep emails in my inbox as reminders to do something about that email, follow up, a task, etc. But that meant my inbox was messy and I didn't always know/remember what I had to do with that email and there were no notes for it.
I have been using the clip to Evernote add-on for Outlook to save and store important emails in Evernote, but now I send them all there.
For my personal email, all emails I want saved go to Evernote and my personal notes. My personal email is pretty empty.
For my work email, I save all important emails, with the attachments, to notebooks based on what project they go with. Any email I save also gets moved to a folder in Outlook for backup reference.
For emails that require me to do something, I clip them to Evernote, and put a link to the note on my task list. This way, they are always on my task list so I don't forget them, and I can add other notes and information to the note for reference. They are better organized, easily searchable, and I can link them in other notes.
I have a clean inbox, all emails are organized (and with additional info) and set so I won't forget about them.
See also:
My Workflow as CIO - includes heavy use of Evernote
Evernote for Education Resources and Uses