Quoting from the rPath official announcement:
rPath, provider of the first platform for creating and maintaining Linux software appliances, today announced it has been notified by Congressman Brad Miller’s office that it is a recipient of a $100,000 Small Business Innovation Research grant from the Department of Energy (DOE).
rPath will use the grant to enable its rBuilder platform to create Xen virtual machine images for deployment in grid environments such as the Open Science Grid.
…
rPath’s virtual appliance technology solves this problem by combining applications with their operating environments in virtual containers which can be run on any available grid…