Here’s a simple Applescript program to create The Hit List tasks from Mail.app mail messages. It will create them in the Hit List Inbox with a start date and notes taken from the body of the mail message.

tell application "Mail"
    try
        set theSelection to the selection
        if the length of theSelection is less than 1 then error "One or more messages must be selected."
        repeat with theMessage in theSelection
            my importMessage(theMessage)
        end repeat
    end try
end tell

on importMessage(theMessage)
    tell application "Mail"
        try
            set theSubject to subject of theMessage
            set theDate to date received of theMessage
            set messageURL to "Task created from mail message:%3c" & (message id of theMessage) & "%3e"
            set theBody to messageURL & return & return & the content of theMessage
            tell application "The Hit List"
                tell inbox to make new task with properties {title:theSubject, notes:theBody, start date:theDate}
            end tell
        end try
    end tell
end importMessage

Copy the above text or download the script file.

I use it by setting up a keystroke using Spark that only applies in Mail.app. It makes it trivially easy to create tasks from mail messages.

If you haven’t seen The Hit List yet I highly recommend it. Not only does it work well but it’s even beautiful to look at.

Updated: Used Andy Kim’s version with the single addition of the start date.