Ask MetaFilter | Community Weblog: "Alternatively, just delete your old mail, since you know you're never going to look at it again anyway.

I have a folder called 'Saved Messages' into which I drag messages I explicitly deem worthy of saving. Most everything else gets automatically deleted no more than 90 days after I receive it -- sooner for some folders (e.g. spam only lasts a week). There are a few folders I prune manually (e.g. folders for particular projects I'm working on). Periodically I even prune the 'Saved Messages'; I probably don't need those registration codes for Mac OS 9 shareware anymore, for instance.

Attachment to things you don't really need is the root cause of suffering. Letting go is the path to contentment."