Mozilla has released a public beta of Firefox "Lorentz," a test version of Firefox 3.6 designed to minimize crashes by running Flash, Silverlight, Java, and other plug-ins as processes separate from the core browser.
The open sourcers call these "out of process plug-ins," or OOPP, and they're also under test with the developer preview that will eventually morph into Firefox 4.0. Lorentz will be rolled into a new incarnation of Firefox 3.6 dubbed version 3.6.4, which - according to the latest Mozilla Platform meeting minutes - is scheduled for official release in early May.
For Mozilla, this is a new way of doing things. In the past, new features like OOPP were saved for major updates (Firefox 3.0, Firefox 3.5, etc). But after the release of Firefox 3.6, the open sourcers vowed to roll fresh features into maintenance releases as soon as they're ready.
With OOPP, a shim layer executes the Firefox plug-in API, keeping it separate from the browser proper. If a plug-in crashes or freezes, Firefox loads a page that says so and sends a crash report back to Mozilla. If you then reload the page, the plug-in relaunches.
Lorentz is available for Windows and Linux. You can download the beta here. ®