I agree: email bankruptcy is the way to go. If something is more than a week old, it's too late to deal with it by email anyway. Remember, there is ALWAYS more than one copy of an email and the person who sent it to you can send it again if they really need you to act/reply.
Tips that worked for me:
Disable your email notifier, unless you are required to reply to all messages immediately (most offices don't expect this). Check it once an hour. Don't let email interrupt your workflow.
Use screening. Don't give your work email address to friends/family. If they already have it, change it.
If co-workers routinely copy you on things that aren't within your range of duties, or if it's a non-hard-copy-worthy exchange, read once, reply if necessary, and immediately delete.
Set up folders for things that pertain to you (HR stuff like reviews, continuing education, compliments on your work, etc can go in "personal"), to your immediate supervisor who may expect you to keep copies so they don't have to, or for office/department procedures. Move emails that fit these parameters into the folders.
If you print out an email for action, or send a reply, delete it from your in-box (or move it to the appropriate work matter folder, if you have a document management system). Match it to the hard material you need to do the job or place the hard copy in the file, but only if needed/required for records retention policies.
I used to get upwards of 150 emails a day in my job managing a small law office. Every single one required an action or a reply. To me, the press of business was unmanageable if I let more than 20 items build up in my in-box.
Good luck!