Priorsmart Patent Search Engine
This one was a neat surprise. It seems to be a very nice meta patent search engine. I normally would frown on this type of search, but the format and search procedure is so user friendly and simple that it really sticks out. You can find it here, at http://www.priorsmart.com/
The test won't really work for this one, because it's just examining other patent search engines. It searches the Patent Office's active patent database, its pending applications and the Google patent database. It also includes three worldwide options: WIPO, PatentLens and Espacenet. I personally didn't have much more luck with the worldwide ones, at least beyond what the US Patent Office had to offer, but it's a nice inclusion for easy global checks after you run through US databases. It also offers links to the patent databases for many other countries, if you need something specific.
The reason that I liked this one was due to its search process. As you should be able to see in the screenshot, you can input search terms and tell it to look for the terms in the title, description, abstract, etc. Clicking on any of the four tabs to the right or the country tabs at the bottom will pull up the advanced search from that database for your specifications. Best of all, it saves your specifications, so you can quickly search all relevant databases. It's a nice meta search option, but you will need to know what you're looking for. Google will still probably be a better starting space if you just want to do a quick search.