I used to work in a line of work where we were required to keep a time sheet. We had to record in fifteen-minute increments everything that we did during the day. Especially because of the fifteen-minute increments, this felt obsessive-compulsive to me and I vowed that I would never keep a time-sheet again.
It was just about a year ago that I started to keep a time-sheet. I was told about it on a Christian forum. I noticed, as a new minister, that it's possible to just keep working and working and that I often do. Also, it's possible to feel guilty about all the people you have yet to visit; there is always someone who needs visiting.
I was told. 'Keep a timesheet. I use Keep it Collared'. This is a piece of 'freeware' that is specifically designed for clergy and that can be readily downloaded from the linked site.
I promptly downloaded 'Keep it Collared' and I realised that I'd already worked 64 hours that week. No wonder I was tired! That gave me permission to relax and not work. At the moment, I've had several weeks where it has just not been possible to have a day off, but just recording my working time helps me to take a bit of rest when I have a bit of a window.
European users need to be aware that, in order for the spreadsheet functions to work, you will need to set your entire operating system to the American date standard (where 13 April 2008 is 4/13/08 instead of 13/4/08). This is a slight drawback, but I personally think it's worth it.
I'm not yet using the new Beta version of the spreadsheet so I don't know how different it is from the 'old' version, but my version not only counts my weekly hours, but it allows me to set my 'vacation' days, my reading days, how many Sunday's off I'm allowed and minimum and maximum weekly working hours. It will also accrue 'comp time' if you want it to.
For me, I've found that it's main use is actually to stop me feeling guilty and to allow me to slow down when I need to. I'm sure it could probably also work for other professions although the features are specifically geared for clergy.