RescueTime is a very comprehensive software if you'd like to be mindful about how you spend your working time. Though the free version is adequate, the paid version allows you to log offline time (e.g. meetings.) in which you were working but not actually spending time at your computer. The Productivity Score is also useful- and very easy to navigate.

RescueTime allows me to get an in-depth report on the amount and time of use of the various sites and software installed on my computer automatically. The software gives the motivation to work on software / productive sites and less on software/sites that waste time. The report allows me to give more accurate working time to my clients.

I like the concise data reporting and presentation.