Are you a freelancer or working on a project where you need to track your time? Check out www.toggl.com to boost your productivity. You can create projects, add clients, and even timesheets/invoices (in premium). I really like the simplicity of Toggle and the fact that there is a Web, Mobile, and Desktop app. The cool thing about the desktop app is that you can schedule a timer to start in case you are someone who tends to forget.
Overall, toggl is my favorite tool to use when working on freelance projects. Whether I'm working on some business cards, or a big web project, I know that toggl will help me manage my time and make my life easier.