"Apple has received a patent for the dock utility for launching applications in OS X. Yes, the dock has been around for the better part of a decade, but Apple applied for the patent back in 1999 and didn't receive it until this week. The patent describes an interface for consolidating frequently used items in a "userbar." It also covers the way that items are magnified when you scroll your cursor over them."
Source: http://www.downloadsquad.com/2008/10/08/apple-receives-patent-for-the-os-x-dock/