It's really hard and risky to make money in the geophysical world (just think how much time and money Tesla has to spend making actual cars). Uber's tech platform is notoriously simple, with one estimate suggesting it got up and running for under $2 million. So how does it spend that $1.2 billion? Acquiring drivers, customers and market share, along with incidentals like cool offices. Uber is nearly a pure customer-facing machine that's infinitely scalable, which is probably part of what has those private investors so excited. Its a**ets either don't exist or, in the spirit of defining your own financial metrics, maybe it's worth more than $40 billion.