QuantumMgr is a an open-source time quantum manager.
Sounds fancy, but it's really rather simple. The purpose of this tool is allow you to keep track of tasks ("projects") - namely the time you have spent doing any given task.
The main interface window offers a series of timers -- one for each project you want to track. Using the controls beside each timer you can indicate which project (if any) you are currently working on.
The software keeps track of all the time fragments (quanta) you have worked and allows you to "bank" them at regular intervals or on an ad-hoc basis.
But that's not all! The interesting feature that elevates this from a simple GUI "widget" is its graphing functionality. Once you have accumulated a set of quanta, you can generate graphs and statistical analyses to visualise your productivity level over time.
- Uses your system's monotonic clock where possible, making it immune to forced time changes (e.g. DST / timezone changes, or user time adjustment).
- Manual "bank" feature to commit the current accumulated time to the database and forget. Useful for sending invoices to clients after a batch of work is done.
- Auto banking at regular intervals is also possible. You might want to track how many hours you spent studying on a weekly basis, for instance.
- Graphing, tabulation and statistics generation.
- Portable -- runs on just about any reasonable modern platform.