This is going to be very cool…
Some may have noticed the “Turbo” link in the upper right corner of the admin area. (Remember when computers used to have a Turbo button?) Behind it is a new feature of WordPress.com, support for Gears.
Gears? It is a browser extension like Flash or QuickTime/Media Player. However Gears works with the browser to enhance web based applications. It can create local database and file storage, and run JavaScript in the background to update them without slowing down the browser.