While watching James Walker talk about OpenID and user management in Drupal, I checked out his blog (and subscribed, on the basis of recent posts).
One of his recent posts was on Fluid: Desktop Web Apps.
If you’re a Mac user (right now this is Mac OS X 10.5 or greater app) and you rely on web based applications, you’ve got to check it out at fluidapp.com.
It’s webkit based, but otherwise like Prism or Adobe AIR in letting you create a desktop-app like presence for a web app – a single purpose embedded browser with a doc icon, notifications, and other OS level features.
It’s free (as in beer) but not open source (as in freedom).