It depends on what you do. Personally, I'm a pretty meticulous filer, I keep lots of paper and digital records, filed in filesystems so I can figure out wtf hap

It depends on what you do. Personally, I'm a pretty meticulous filer, I keep lots of paper and digital records, filed in filesystems so I can figure out wtf happened 3 or 5 years ago. (I'm a manager in a large IT organization) Ancient email is often important to establish the context surrounding decisions that have multi-year impact. Also, many folks use email as an ad hoc general filing system. They rely on search to find information, and email is often the ONLY system available with reasonable search ability. If you're in a small company, this will sound insane. But in a mega-sized org like the one I work in, its essential.