Google released the beta version of Google Patent Search, which makes it easy to search the full text of the U.S. patent corpus and find patents that interest you.
"Google Patent Search covers the entire collection (over 7 million patents ) of patents made available by the United States Patent and Trademark Office (USPTO) from the period 1790s through those issued in the middle of 2006."
Google Patent Search uses much of the same technology that powers Google Book Search, so you can scroll through pages and zoom in on text and illustrations just like you can with books. Start your exploration at www.google.com/patents or visit the Advanced Patent Search page to search by criteria, including patent number, inventor, and filing date. You can view images of original patents online.