Here's what I want: I want a program that sits, inactive, on my desktop (not running at all), and when I double-click it, it launches, and adds the startup time to a logfile. Then it leaves something in the system-tray-thingy which clicking on brings up a menu to stop logging the time (and exits the program). At startup, the program runs in a special mode, checks the log, and if it shows as currently active, launches itself, adding a new specially-marked startup time; now logging can be stopped in the normal way. The system allows you to manually edit the log when you forgot to close it or open it or whatever, and then a separate program computes and adds up the time. Maybe while it's open it writes to the log every fifteen minutes or so, so if you crash and then go away for ten hours, it becomes obvious you weren't actually working during those ten hours. In fact, come to think of it, maybe the best thing to have it do is just write an entry to the log file every five or ten minutes or so, and just ignore start and stop times; just use every such entry as an indication of five or ten minutes spent on the project. (I only really care about accurate to maybe the half hour.)
All the programs I've found do things like: have multiple simultaneous timers, require a separate 'save' step to add it to the log, be an actual window that shows you time elapsed (I don't need yet another window to manage), etc., that just makes it way tedious to use them. If I have to click a lot, I might just as well write down the start & stop times by hand, rather than rely on the computer.
It seems unlikely, but any suggestions?