Yes, it’s an internet holiday that encourages us to clean out our email.  It’s also an opportunity to take a few minutes to organize emails and do a bit of winter cleaning.  
I recognize how overwhelming email can sometimes be.  Work emails seem to continually flow in, and keeping up with personal email is just as challenging.
Here are some tips for cleaning your inbox, as well as managing future emails:
First, try using the “Two-Minute Rule” (a concept from David Allen, the author of Getting Things Done) when you read your mail.  If an email takes you less than two minutes to read and reply to, take care of it right away – even if it’s not a high priority.
Second, create folders.  As you reply to emails, file the email in the appropriate folder.  I also file my replies, just in case I need to refer back to something.
Here are some tips for managing emails on a regular basis:
If an email does not need to be filed, delete emails that don’t need your attention.  Be sure to empty your deleted emails folder.
Use “Rules”.  Most email programs, including Outlook and Gmail, allow you to create rules that will sort emails into a folder as soon as it arrives.  This allows you to receive the email and refer back to it when you have time – keeping your inbox free of non-essential emails.
Schedule a time to review and respond to emails.  It may sound funny, but having a scheduled time each day to review emails will increase productivity.  While you may still have to respond to critical emails throughout the day, you will feel less pressure if you’re able to review emails at a regularly scheduled time.  I have found reviewing emails early in the morning over a cup of coffee, and then a quick glance at the end of day, really helps reduce the number of messages that collect in my inbox.