One of the new features in Apple's Safari browser is the availability of the various auto-fill capabilities. These have been done before in many browsers, but there are some very unique implementations to the version that the folks at Apple have brought us.
My favorite, by far, is the integration with my personal address book entry (the one that you marked as "Me" when you put yourself in the book). First, it's nice that Safari uses the latest information, but the coolness doesn't stop there. The best feature is that it knows the difference between your home and work information and will automatically change from one to the other if you start to type the other information. So, start filling in a form and get your office information. However, you wanted your home info. Just type the first few letters of your home address into the address field and all of a sudden it changes the City,State,Zip,email, and phone to the right thing.