Spam and glurge emails from friends I delete, the rest is filed. I like both Outlook and gmail (but use the latter mainly at the moment) because they make establishing categories easy. Because I deal with both professional and volunteer organisations, I find the filing – and non-deleting – essential for record keeping and keeping track of data. Essential archive stuff, particularly to do with my historical society, I print off in hardcopy.
I keep everything (except spam in my personal mailbox) and rely on full text search for retrieval.
Work mailbox (Lotus Notes): about 81,000 sent and received mails in active database, back to November of 1995, about 317,000 received mails in spam/automatic status message database.
Personal mailbox (Gmail): about 8,300 sent/received mails back to 2005 plus 183,000 spam mails from the last 30 days.
Both Notes and Gmail are very good with full-text indexing.
I’m the complete opposite. I’m a deleter. I’ll file certain emails if I think I’m going to need to refer to them later.
Two main reasons for this:
- I hate clutter and a large inbox is clutter.
- If someone should get access to my email, I’d rather them not have access to a lot of emails from the past.
I keep things that I might need to refer to later (purchase info, instructions) and delete most of the rest. And even though I have gmail, I still delete a lot of it, because it’s either junk or glurge-forwards from family.
I’m anal, save important stuff in two different places, sometimes three or four. Two in house and two online.
I delete spam and glurge, copy and save wanted pictures out of email. Especially linked images that might go away.
Total time out of the day managing email = about 60 seconds.
I have no business emails and only get about 10 - 60 spam a day.
Two active email accounts.
Thanks! And thanks for the kinda sorta welcome as well. 
I like to keep the Inbox empty.
I keep a few e-mails in folders – addresses, some book stuff, passwords and subscription info, some jokes and photos.
Right now I’m keeping correspondence relating to a book that I preordered and paid for in 2004 – a two-volume limited edition compilation of the best horror fiction of the 20th century. If I don’t keep that e-mail, I’ll forget that I’ve already paid for it and would probably buy it again. If it ever gets published.
I’m also keeping an e-mail from ABC-TV. I referred a family for Wife Swap, they’ve been interviewed, and if they appear on the show, ABC owes me $1,000.
I save all emails from my accountant. Also, whenever possible, I try to ask my questions to them via email. It helps ALOT when they ask were a certain file is, I tell them that they told me to shread it, they say they would never have said that and I can resend their email stating that back to them. But that’s pretty rare. Even so, since what they are telling me IS legal advice generally, I try to keep them all near by.
I save everything (that isn’t spam).
At work, because I have to. I’m in IT, doing both support and compliance; I frequently have to go back several years to find the message that (a) describes how something broke, when it breaks again, so we don’t have to reinvent the wheel; (b) contains somebody’s commitment to a plan of action, so I can throw it back at them when they try to claim ignorance later.
Personal mail, I keep not necessarily for the messages, but for all the addresses in the cc lines. Never know when you’ll need to get a hold of somebody obscure.
If it’s work related, it may or may not get saved. Announcements, news, dailies… I read em, then trash em. Important things I might need to reference in the future, saved. Anything I think I might need a paper trail on, saved.
Personal email comes through Gmail. Notifications (“Your item has sold,” “Your statement is now ready,” “Your payment has processed,” “You have a message on Facebook,” etc) are deleted without being read. Gmail does a hell of a job handling spam, so that all goes to the spam folder. I’ll empty it occasionally, or it empties itself I think. Anything else important or memorable gets saved.
One similarity between the two, though, is that I refuse to let stuff sit in the Inbox. The Inbox is for things that are coming in, to either be deleted without reading, read and saved, or read and deleted. My work email has 14 folders for various people/departments/categories. Gmail doesn’t have “folders” but rather, labels and archives. Labels I have now are for my cellphone (a back and forth with customer service), Wedding things, improperly addressed work mail… you get the idea.
Whenever I see a co-worker open up their email and the Inbox has pages and pages of crap, I just want to smack them. Don’t know why.
I have email going back to the late 90s, when I used Eudora to access the stuff from the school mainframe. Around the first of the year I’ll enable a smart search I have set up to grab everything older than 6 months, and throw those messages into an archive. I strip out non-essential attachments before I archive anything, which is effectively everything considering that if it was important I’ve probably already saved it to an active work folder anyway.
Keeping most of my mail makes it easy to refer back to earlier conversations. Searching in OS X is really fast, so dealing with hundreds or even thousands of messages isn’t a problem since — aside from the stuff I filter out — I don’t have to actively organize it. Same if I’m using a web interface for my email; both Yahoo and Google have pretty good search technology. Perhaps you’ve heard of it? 
I don’t keep absolutely everything. I have several filters to sort incoming messages into various folders. Advertisements and promotional stuff from Amazon and other online retailers get deleted after I take a quick look at them, or after a month, whichever comes first. The month cleaning is automatic, handled by filters. Same with the couple of newsletters I’m subscribed to.
Junk mail has to get past two sets of filters: Yahoo or Gmail’s filters, and Mail’s filters. It has been years since I actually got spam in my inbox. Both those services are really quite good about getting rid of junk mail. I get maybe a message a month that gets as far as being downloaded to my computer, where it’s promptly shunted into the Junk directory.
I ditched Hotmail around 2000 or 2001 when I was getting more junk than mail (not nice at all when I was on dial-up access) and Hotmail didn’t play nice with Japanese text encoding. My friend still uses Hotmail and complains about how much spam he gets :rolleyes: Duh, why do you think I sent you the invite for Gmail a couple of years ago?
I save confirmation of payments as well as some letters from friends… that’s just about it.
I have a few emails from my father that I’ve kept; not that they say much of anything, but since he has passed away, sometimes I do go back and look at them.
Yahoo is trying to compete with Google’s Gmail, which promised you’d never worry about saving too much because they had fast searches.
But for me, most email is too much. Keeping yesterday’s news forever is not a good thing. It’s just more slag to sift through. Old junk will appear at every search.
I hate to search, I like to just keep enough that I can look and find something.
And when I erase something I never have to deal with it again. Why should I? I would never do that at work, want them to save all my wastebasket contents forever.
I sort “important” stuff into relevant folders, and delete the rest. I have about three years of emails from two “recipe-a-day” sites. 