- RescueTime is a really solid product that has been available for years and reliably tracking my desktop productivity. It logs activities silently in the background, and you can come back to it later to see what you were working on. It used to have automatic project tracking (automatically assigning activities to clients based on keywords), but unfortunately that's no longer available AFAIK.
I love Rescuetime and have used it for more than a year. Affordable and a great way to manage how you are spending your time. It's not yet a full solution, and will need to expand to iOS mobile and also provide a more robust solution for offline tracking.
Extremely helpful tool if one struggles to improve his/her daily productivity.
- I've recently discovered Timely and its "Memory" feature (which relies on a Desktop client for logging activities, capturing window/tab titles, just like RescueTime) seems like it could help further for producing timesheets, as it offers a nicer workflow for turning the raw "Memory" logs into total hours worked for a given client.