Adobe recently created a media buzz with the announcement of a cross-platform Web-enabled runtime environment, code named Apollo. The environment allows developers to create applications that run directly on the desktop while using content from the Web. Adobe has built Apollo to leverage existing technologies such as Flash, Flex, HTML, and AJAX. Apollo is an amazing concept, but it is not a new idea. Sun Microsystems released Java Web Start in 2001, and the Mozilla Foundation invented XUL when it created Firefox. There are also several startups entering the market. All of their products are geared do the same thing: bring Web applications to the desktop.

Source: Webtop software development: Combining the desktop and the Internet