On the 43 Folders website, Merlin Mann suggested that email authors should "consider adding functional text headers to the top of the body [of their email messages] outlining the exact nature of the message." In his article "Writing sensible email messages," Mann proposed these headers should look like this:

This email is:   [ X ] actionable [  ] f.y.i.     [  ] social
Response needed: [  ] yes         [  ] up to you  [ X ] no
Time-sensitive:  [  ] immediate   [  ] soon       [ X ] none

I wrote a series of templates implementing these headers for the Quicktext extension for Mozilla Thunderbird. I am making these templates available to you, free of charge. Here's how to install and use the Action Email Headers:

1. Install Mozilla Thunderbird as your email client.
2. Install one of two Thunderbird extensions:
   
   • Quicktext (free)
   • Quicktext Pro (commercial)
3. Download headers.zip. Extract the archive to obtain headers.xml.
4. Import headers.xml into Quicktext (Tools->Quicktext, then File->Import->Templates).
5. Now when you compose a message, you'll notice three new menus in your Quicktext bar:
   
   • Actionable
   • F.y.i.
   • Social.

   These are your selections for the "This email is" category. Under each menu, you are given the choice of 9 combinations to complete the headers.

Any additions/corrections to the headers will be posted on this page. Please report any incompatibilities to David Fisco.