Keystone adds custom keyword searches to Safari. Type simple queries such as "wiki Mac OS X" directly into the address bar, and Keystone will translate them into searches in this case, opening the Mac OS X page on Wikipedia.
Keystone works along side of Safari's own completion system, which means you can choose which completions you want to use. It also includes autodiscovery, allowing you to turn any search field into a Keystone shortcut.
