1. A computer comprising: one or more processors; logic stored in one or more storage media and executable by the one or more processors, wherein the logic is configured to cause the one or more processors to: receive a first request for a desktop image comprising a collection of files; segment the desktop image into a prefetch set, a streaming set, and a leave-behind set, wherein: the prefetch set includes a smallest subset of files, in the collection of files, that is needed for a boot of a computing device without requiring retrieval of additional files; the streaming set includes those files, in the collection of files, that are to be automatically transferred after the boot; the leave-behind set includes those files, in the collection of files, that are not automatically transferred after the boot and are transferred only when specifically requested; and in response to the first request, send the prefetch set to the computing device; after the prefetch set has been sent, receive a second request for the streaming set; in response to the second request, send the streaming set to the computing device; receive a third request for a specific file included in the leave-behind set; and in response to the third request for the specific file, send the specific file in the leave-behind set to the computing device.