We identify a new capability for mobile computing that mimics the opening and closing of a laptop, but avoids physical transport of hardware. Through rapid and easy personalization and depersonalization of anonymous hardware, a user is able to suspend work at one machine and to resume it at another. Our key insight is that this capability can be achieved by layering virtual machine technology on a distributed file system. We report on an initial implementation and describe our plans for improving efficiency, portability, and security.