A noteworthy beta site, Google Patent Search is a remarkable development. Google has added its sophisticated search appliance to the universe of patents granted by the US Patent and Trademark Office since the 1790s, more than 7 million.
Of course, you can use the one-box wonder that is the standard Google search. A search for the humble shoelace ties into 538 patents, including a variety of shoelaces, shoelace covers, shoelace retention devices, shoelace warning systems, and shoelace adjustment mechanisms.
Or step up to the Advanced Patent Search to look for patent numbers, inventors and assignees, classification numbers, and ranges for issue and filing dates.
For more information on patent searching, see the step-by step guide at the UW Engineering Library website. See also the Gallagher guide on Patent Law Resources.