I really like using keyboard shortcuts – they save time and you don’t have to move your fingers from the keys to the mouse. Not that much time-saving on a laptop, but on a desktop computer it can be really nice to learn the key shortcuts. Most programs have keyboard shortcuts for the common options. Two programs for Mac you may want to download are Quicksilver (do anything on your computer by pressing Cmd + Space) and Witch (switch between open windows, not just open programs)
I’ve gotten a lot better at forcing myself to use the keyboard with Firefox. I simply took out the navigation bar and the bookmarks. The bookmarks are still there, I just open them with Quicksilver.