This is my new favourite shortcut to avoid using the mouse when browsing the web. Just simply type the following on a Mac in Safari (lets say version >5.0)
⌘ + ⌥ + f (Command key + option key + 'f')
Your cursor will then jump to the search box so you can search for anything you wish on Google (does anyone really use anything else? ... perhaps DuckDuckGo?)
It even works in Chrome (I do not care for many other browsers other than these two- they take care of well over 90% of my browsing)!