Task logging feature

The reason I got interested in this project was that my girlfriend and I
are independant contractors.  We want to keep a very close eye on what
we do throughout the lifecycle of our projects.  Thus, she suggested
that I write an application that pops up a "what have you done this
hour" query once per hour.  The data entered into this query window will
be used along with the project management tool (MrProject) to keep
detailed notes about the work that was done on the project.

Perhaps this query window would have a set of drop-down menus that would
let you choose which aspect(s) of the project you were working on. 
Notes entered could perhaps be aded to the notes field of the project
along with the contributer username and timestamp?

Is this the right place to start implementing this tool?  Or should I
start a different project which uses an mrproject API to modify the
notes field?

I've got quite a few ideas about what can be included in such a tool.  

Is anyone interested in heraing them?

C.J.