Ideal Email Client

I'm fed up with the way I currently handle my email and am about to look for some better solutions. Before I do I want to make a note of the problems I'm facing and what I think the ideal solution would be so that when I get some free time sometime next year I can start building a platform that meets my needs (and therefore probably everyone else's too).

• I'm subscribed to about 20 mailing lists and so get hundreds of emails a day. These are filtered into various folders and every now and again I check each to see if there is anything relevant to me. This ends up in me missing lots of important emails or not getting a chance to answer a pertinent question until lots of other people have chipped in and confused the issue. As a result some people just cc me into emails sent to lists. This doesn't help either because then when faced with a huge inbox I can't instantly tell who is writing to me directly and who has just cc'd me int an email which probably isn't such a high priority. The result is that I miss import ant emails directly from people who also contribute to the mailing list communities.
• Emails don't normally fit nicely into one category so putting them in folders is really very little use. Instead tags are needed where emails can be tagged according to various criteria. Tags themselves can be grouped so that related tags appear together in the interface. When you receive an email you can then interface wise you just click on the various tags related to that email and they can fly off the tag list onto the email. You can also drag and drop them to change how you want to categorize the tags. The main interface to the emails then isn't the date or the sender but the tag.
• I work with the same people on different projects so there is no easy way to categorize messages according to the project. What is needed is a way for people to categorize the emails they are sending. One way would be to send emails to different addresses depending on the project. Better would be to provide the same tag interface for sending as used for taging mails in the inbox then the recipient can also use those tags to categorize the email.
• When looking through emails three processes are happening: prioritizing, categorizing and dealing with. Interfaces need to be able to deal with those three different modes of operation.
• Emails need to be accessible via a web interface as well as via POP and IMAP. The web interface needs to minimise bandwidth so the email can be browsed over a crap connection at a client. It should also support offline access via something like Google Gears.
• Emails from people you haven't heard from for ages need highlighting so that you don't miss them because when scanning through your inbox unfamiliar names can easily missed. This means the email client needs built-in contacts lists supporting tagging.
• People sometimes just cc you into emails so that they don't have to explain what's actually going on directly to you. This isn't helpful because you can rarely pick up the deeper politics behind a situation from email cc's and you end up treating all emails from the related parties with the same lack of interest when occasionally the emails are really important and relevant to you.
• You need to be able to select which email address the email appears to have come from even if it is from a different account. The default should be the email address the email was sent to.

OK, that's the rant over.. better get back to dealing with some emails...

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