If you use FreshBooks - the excellent online invoicing and timetracking application for freelancers - you may find this Safari extension useful. One click on FreshTime's toolbar icon is all it takes to open a handy FreshBooks timer window. Even better, if you let it save your username and password, FreshTime will automatically log you in. Finally, FreshTime will remember the timer window's position, so you don't have to move it every time.
Mac OS X 10.6,
Mac OS X 10.7