Greetings, I would like the following functionality for my email client, and welcome ideas and suggestions!

I send a lot of email that I hope will be answered. Occasionally I don’t get an answer, and I’d like to follow up if that’s the case. What I could do is keep track of every email that I send as a todo item, and then check off that todo item when I get a reply. But the common case is that I do get a reply, and I’d like to optimize for that case; I’d be doing a lot of bookkeeping otherwise. I’d only like reminders when I don’t get a reply.

My ideal system would allow me to send an email and set some sort of reminder (perhaps cc: another address?) that reminds me in a designated amount of time only if I don’t get a reply. Currently there are services like followup.cc that partially fit the bill: I can cc: a message to 1w@followup.cc and in a week, I’ll get an email reminder. But, followup.cc has no access to my mail stream and can’t watch for replies; what I’d like instead is something that watches my mail stream for Message-IDs and only reminds me at the designated time if it hasn’t seen the initiating Message-ID.

Any pointers to anything like this / thoughts on how I could implement it? I am on OS X; I use the emacs mailer "Wanderlust" primarily, but Mail.app runs in the background, so my backup plan is writing it in AppleScript and running it in Mail.app, I suppose. I don’t have access to procmail, which might have fit the bill as well.

Erik Hetzner on the Wanderlust list suggested using imapfilter; the fine folks at indev (power tools for OS X Mail.app) suggested the following: http://support.indev.ca/discussions/suggestions/1590-query-for-functionality-keeping-track-of-follow-up-emails-does-your-product-do-anything-like-this