Installing the gadget is easy—just double-click on the downloaded file to add it to your sidebar, and use the wrench icon to add in your Google account details (works with Apps too). Once you've authenticated you can choose which calendar you want to send your time tracking data too. (It's probably best to create a new one to keep from cluttering your regular schedule.) At this point you can start tracking your time by simply typing what you are working on and clicking Start; when you're done, hit Stop to save your data up to Google. At the end of the day you can check the Agenda view in Google Calendar to see a nice list of everything you worked on throughout the day.
The gadget has a few issues—most noticeably it's too wide to fit in the sidebar so you really have to use it on the desktop, but the bigger problem is the lack of automatic sync, requiring you to remember to use the Stop button to save. The benefits of being able to easily track what you are working on and save to the accessible-everywhere Google Calendar outweigh the problems—and make this worth a look for anybody looking to keep better tabs on their time.
gCalTasks is a free download for Windows 7 or Vista users. If you are looking for a hands-off, completely automated solution, take a look at previously mentioned Productivity Meter or Slife instead. Do you have a preferred solution for tracking your time? Share it i! n the co mments.