Container data centers have been in the headlines recently, but are still academic for most companies since vendors won’t list or even provide a firm price, likely expecting a similar markup as blade computers.
I really like the overall container data center concept, especially for operators with available real estate and power.
Every neighborhood block in Silicon Valley has a Pods storage container in the front yard. Why not your own data center? One could even do free cooling in the winter. 
datacentermap.com: Container Data Centers
Container Data Centers: “Waiting for Godot” meets “The Price is Right”
Cringely: Google-Mart: Sam Walton Taught Google More About How to Dominate the Internet Than Microsoft Ever Did
wikipedia: Intermodal Container
wikipedia: Sun Modular Datacenter
Dell XS23 Cloud Server (likely for Microsoft Azure)
theregister.co.uk: Mobile internet to eat world, apparently
register.co.uk: Microsoft researcher obsessed with white trash data centers
cnet.com: Grid storage gets updraft from auto batteries
