Search the Web from Mac OS X Finder, TextEdit, and Preview
Mac OS X and several default apps have a built-in ability to quickly search the web. Highlight any text in the Finder, Preview, or TextEdit, and then hit Command+Shift+L to launch Safari with a Google search for the highlighted text selection.
The web browser will be set to Safari regardless of your default browser settings and doesn’t appear to be customizable. However, you can select either Google, Bing, or Yahoo as the search engine for the keyboard shortcut by going into Safari’s Preferences:
Other apps beyond the three mentioned likely have the same ability, but the Command+Shift+L keyboard shortcut in Safari opens Reading List rather than searching the web.