Hosting provider, Joyent, recently announced an early testing program for Slingshot, a framework that enables the development of Rails applications that function both online and offline.:
Joyent Slingshot allows developers to deploy Rails applications that work the same online and offline (with synchronization) and with drag into and out of the application just like a standard desktop application. Joyent Slingshot is a simple and lightweight mechanism to cleanly synchronize online and offline data. You, as a developer, can provide an ActiveRecord transport layer allowing easy customization of the data that gets synced to your application’s who, and when, and how. With the addition of about thirty lines of code, your Rails application can sync data from client to server. With another thirty lines of code you synchronize have file-based data.This news was picked up by Jeff Mancuso on the magnetk blog, who added additional detail on how Slingshot works. Slingshot is not the only recent framework to target desktop applications using web technologies. Adobe's Apollo runtime uses Flash, Flex, HTML, and Ajax to deploy desktop-based rich internet applications. SitePen released the at the beginning of the year which enables browser-based applications to be adapted for offline use. Even Firefox 3 adds an offline datastore that applications can access while offline.