if email is to become the medium for instant messages and "phone call" messages, some things will have to change. if someone phones me (or sends an SMS), they

if email is to become the medium for instant messages and "phone call" messages, some things will have to change. if someone phones me (or sends an SMS), they know they'll reach me right now because my mobile phone is always on. if someone sends me an IM, they hope to reach me now, but waiting is acceptable, because i might not be at a computer or my IM client isn't running. if those two are to work via email, i'd need a second address that acts like a phone number. people trying to reach me on that address can expect to get through right now. of course, if you abuse that privilege, you end up on my killfile and i'll only notice your messages later. IM-style communication would run on the old email address. when i'm online/available, you can probably chat with me in realtime. if i'm not available right now, i won't even know about the new messages right away, but i'll get to it later. there were several occasions when i was emailing back and forth with someone within minutes. seamlessly turning that into a chat session would be awesome, but email still doesn't have sub-second delivery times and email clients still display emails like big, important letters and not like lines of a chat session. i think there can be an UI that looks good for both chat sessions (many small messages) and emails (few large messages).