A command-line organizer for getting things done

In case anyone hasn't noticed: I have a thing for simple solutions.

So here is the third iteration of my personal to-do tracker. Previous versions held each task in a separate file, possibly along with a verbose description and several metadata fields.

This one is a return to simplicity. As a special note, I am particularly proud of defaulting to the venerable .plan file to hold the task list. I've always wished I had a proper use for it!

From the README:

basic operation

• keep a list of tasks in ~/.plan, one per line. example:

   do something
   do something else
  

• annotate them with due dates as appropriate

  12.7.2010! do something
  do something else
  

• arrange roughly in order of priority
• group tasks by context, i.e. what could be done together

  do laundry
  scrub floor
  
  visit parents
  do something on way to parents house
  do something at parents' house
  

• mark current tasks / next actions

  > laundromat
  scrub floor
  > read chapter on poly types
  

• stall tasks until a certain date

  2010-08-20> bday present for dad
  2010-08-25> bday present for sis
  

• use hashtags to name projects

  code up first prototype of new #watnu
  blog about #watnu on #khjk
  

• watnu will warn when a project has no tasks active or scheduled.
• use generic tasks to keep projects on plan:

  keep blogging on #khjk
  keep coding: #watnu #bitlbeeotr #noooo
  #home #friends #school
  

• multiple date formats allowed. examples (all 1st of may):

  2010-05-01! iso date
  1.5.2010!   german
  5/1/2010!   us
  
  1.5.! german w/o year
  5/1!  us w/o year
  

• delegate tasks to other people, schedule activation as reminder

  10.7.> [mom] do laundry
  [timmy] scrub floor
  

• call watnu to get your current todo list. order and grouping will be preserved from input.
• set PLAN environment variable to use a different input file
• set PLAN="-" to read from stdin

The concepts are my take on ideas from David Allen's GTD. These are some data points on the design:

• Contexts never really worked out for me. Instead of ordering tasks by priority, GTD advocates grouping them by what can be done together. While I agree with that, trying a priori to name a good set of contexts was annoyingly cumbersome.
• It was hard to keep an overview when tasks were scattered around their separate files. This made the weekly review unpleasant.
• Long task descriptions are superfluous. Sometimes there would be a note, e.g. opening hours of a store, but the vast majority of tasks are one-liners. Tack-on notes can be added as a separate feature later.
• Only some things have hard due dates. In general, it is more important when I plan to start something rather than until when I must have completed it.
• Tasks of the someday/maybe category need not be tracked. Keep them in a different file.
• There are always tasks that are definately to do but should not appear on my radar, yet. They might be scheduled for later or simply buried by more pressing matters.

The program is just short of 180 lines of Haskell code. See the README file for build instructions.

NB. I have found it a surprisingly nice routine to print a fresh todo list on a PocketMod each morning, so I'm throwing in a dirty shell script as a free bonus.

Get it here: http://code.khjk.org/watnu/