  Virtual machine images and instances (VMs) in cloud computing centres are
typically designed as isolation containers for applications, databases and
networking functions. In order to build complex distributed applications,
multiple virtual machines must be connected, orchestrated and combined with
platform and infrastructure services from the hosting environment. There are
several reasons why sometimes it is beneficial to introduce a new layer,
Cloud-in-a-VM, which acts as a portable management interface to a cluster of
VMs. We reason about the benefits and present our Cloud-in-a-VM implementation
called Nested Cloud which allows consumers to become light-weight cloud
operators on demand and reap multiple advantages, including fully utilised
resource allocations. The practical usefulness and the performance of the
intermediate cloud stack VM are evaluated in a marketplace scenario.
