How much would it cost to rent a TARDIS for a year?

Owning a TARDIS is like having access to a timeshare anywhere in space and time. It's a valuable commodity, but just how valuable? The speculative bean counters at Centives have decided to take a crack at figuring out how just how much one month's rent on the TARDIS would be. » 3/03/12 3:00pm 3/03/12 3:00pm