You can type many numbers into Google to find information. Here's a list:
Type a product's UPC code, and you are sent to the UPC Database, which gives you manufacturer information about any product.
Type a Federal Express tracking number, and you are sent to a FedEx page that supplies tracking information.
Type an U.S. Postal Service tracking number, and you are sent to a page with tracking information. You can only do it on packages that you can also track through the U.S. Postal Service site, which means this search works only for letters or packages you've sent using a method that allows tracking. For example, if you simply have a USPS number from shipping a package, but didn't pay for a service that offers tracking, such as registered mail or certified mail, the search doesn't work.
Type the flight number of an airplane, including the airline, such as Delta 1098, and you get a list of pages from which you can track the status of a particular flight.
Type the tail number of an airplane, and you see the full registration form for the plane.
Type Patent and then a patent number, such as "patent 5123123", to get patent information about any patent.