For the past four years, every day has brought a stream of emails to my inbox. Some days, this stream resembles a trickle (such as on break, or on the weekend). On the weekdays, it often approximates a torrent. My strategies for diverting and handling this torrent of obligations, requests, and information has changed every so often. My goals in these incremental changes of process are to 1) minimize the time needed to find past emails 2) minimize the mental overhead of keeping track of the status of emails, and 3) minimize the time needed to maintain the system to make 1) and 2) possible.
In the past, I had a low volume of email to deal with, so I had a boring method of handling email: upon new mail arriving, I either replied to it or left it alone. After a few days or weeks, I would get tired of scrolling through my inbox. Some of the emails could be easily deleted or archived in a folder, but there were always some emails that were not yet "done". Perhaps they merited a long and thoughtful response that was yet short and ill-conceived; perhaps they gave details of an upcoming event. The easiest thing to do was to use the inbox as a holding pen until these messages became 'resolved'. This strategy worked well until senior year, when I became wrapped up into so many different events, ideas, and mailing lists that my inbox would still be at 30 messages full after being "cleaned".
I've decided to use this new approach, called the Trusted Trio.
Basically, you segment your email into three categories which explicitly model the lifecycle of an email. I'll call these categories "TODO", "In Progress", and "Archive". The first category is for emails that can't be responded to in a minute or two and need more time to be dealt with. This includes emails requiring long responses, some (external of the mailbox) action, or otherwise require me to do something.
The second category, In Progress, contains messages that require a later follow-up, pertain to a future event, or are no longer TODO but not quite dead yet. If you were to have an exchange with someone to set up a lunch, and were awaiting a reply of their preferred times, the entire thread would go into "In Progress".
The final category is for emails that are done, dead, or most likely no longer alive. Depending on the email client, you can organize this however you like: with a tagging-based email client (i.e. GMail), adding subject tags is a sufficient amount of organization. I use Mail.app and MobileMe right now, so I use folders based on what part of my life the email pertains to. The current subfolders include Research, Personal, Shopping, Class.
My main problem with this new approach is that it gets messy with several different email accounts. Right now I have a half-dozen emails and many more redirection addresses (such as @mac.com, @acm.org, and so on). It is difficult for me to funnel all of these into a single IMAP email account, especially when i'm not in front of my laptop. Hopefully when I start at UW, most of my emails will slowly come by just one or two accounts.