Agenda clock report - adding new columns

[Bernt Hansen <bernt@norang.ca>]

Hi Carsten,

I use the daily agenda clock report to see how much time I've spent on
tasks for today (C-c a a R).  Is there a way to add a column to this
report?  I get a daily clock report like this:

| File       | L | Headline    |   Time |      |      |
|------------+---+-------------+--------+------+------|
| tasks.org  | 1 | Do Stuff    | 0:30   |      |      |
| tasks.org  | 2 | Subtask 1   |        | 0:15 |      |
| tasks.org  | 2 | Subtask 2   |        | 0:15 |      |
| tasks.org  | 3 | Subtask 2.1 |        |      | 0:15 |

where Time is the clocked time.  I'd like to be able to add a column
based on a property (MINMAX) of the task so the report would look like
this:

| File       | L | Headline    | MinMax |  Time |      |      |
|------------+---+-------------+--------|-------+------+------|
| tasks.org  | 1 | Do Stuff    | 1:00   | 0:30  |      |      |
| tasks.org  | 2 | Subtask 1   |        |       | 0:15 |      |
| tasks.org  | 2 | Subtask 2   |        |       | 0:15 |      |
| tasks.org  | 3 | Subtask 2.1 |        |       |      | 0:15 |

I don't care if the MinMax column is before or after the Time data but
it would be nice to display it somewhere along with the tasks.

What I'm trying to accomplish is an easy way to see where I'm spending
too little or too much of my day.  Some tasks I want an upper bound on
time spent (like playing around with org mode for instance) and others I
want a minimum amount of time spent (such as actually working on paid
projects).  For these tasks I would have daily repeaters so they can go
TODO -> STARTED -> DONE and I'll just mark them DONE when enough work
for the day is complete.  The tasks would automatically reschedule for
the next day when they are marked as DONE.

I'm just looking for a quick reminder of
  - don't spend more than this amount of time on task X
  - spend at least this amount of time on tasks Y and Z
each day.

I know other people (including you) have limits on the amount of time
they spend on a task in a day but I haven't really found a good working
solution for this yet that fits my needs.  For a single task this is
easy but I'd like to not have to remember the limits for multiple tasks
-- that's what I use org for ;) to get all these details out of my head.

Is something like this doable?  Does anyone have a better idea for how
to deal with this?

-Bernt