Do you have hundreds of unread emails haunting you but can't delete them because “what if one of them is important?”
Delete them. If you miss something important, you'll find out sooner or later. And you are much more likely to miss important things if your inbox is perpetually full.
After that liberating act, check your email and clean up your inbox(es) daily. Don't read everything. If it's not important, delete it.
If you've signed up for way too many email lists, unsubscribe as they pop up.
You'll feel so much lighter, so much more together and on top of things. You are so virtuous and organized!