Time Clock for CVSTrac
I use this personally to log hours in a user-defined field. (The same field I then use with "Invoicing", not yet released.)
Just read README.timeclock in the tarball for installation instructions.
Latest release: Timeclock 0.6
The obligatory screenshot:
Note that "Listview" mode is enabled in this screenshot, but it is disabled by default in the current release. The CSS needs to be cleaned up quite a bit before it's ready for prime time. Look for it in upcoming release 0.7.