You can't live without it but, boy, maintaining your inbox takes up way too much time!
The sheer numbers of emails in most corporate inboxes is a major culprit, and these days, spam is less the issue as spam filters are getting pretty good.
So what's the answer, since making a 25-hour day is not a practical option?
I see three elements.
1) email etiquette: Businesses need to recognize that email etiquette is at the source of the problem. Overuse of REPLY ALL, and CC are two major culprits. But old habits die hard and changing personal behaviour is a real challenge. UC Cellular took the relatively drastic step of declaring 'email-free Fridays' to make the point. But this will fail until better email etiquette ('netiquette') is established. Not that complicated! Here's 10 steps from Microsoft on the subject. After all it's a win-win for employees (except for those who self define their daily jobs and related job satisfaction as reading and/or responding and/or forwarding every email!).
2) Training. Like any tool, email can be used for business advantage or misused with potentially significant productivity impacts. My favorite is related to emails associated with meetings. I don't know about you, but my calendar is king. I personally am never sure how to change one instance of a recurring meeting without messing up the works! Getting this wrong in the past has resulted in considerable grief. These should be an option to 'revert to old calendar if i mess up', a rough analog to voice conference calling when I say "if I get this wrong, call me back'.
3) Stop the email chain: Not unrelated to the above is the notion of stopping a string of emails on a particular subject and adopting a more appropriate media to close on the subject at hand. For example, launch an IM and then call him/or her. You can do this 'out-of-band' but looking up a name or 'in-band' by simply clicking on it. This is one element of Unified Communications, which makes escalating from email to IM to voice to conferencing a click-away, and the reason for telecom vendors to team with email vendors, as Nortel has done with Microsoft and IBM. UC also includes Unified Messaging which can include listening to your email or reading your voicemail to make itr easier for you. If you think about it, social networking has likewise been invented to solve the inefficiencies of email.
So stop complaining about email overload, lead by example and tell IT what you need.