For instance, Exxon-Mobil has $347 billion in tangible assets while most of Google's value comes from its brain trust and the vision of its leadership. The same could be said of Apple though they do have $40 billion in cash.
In other words, if both companies were offered to you at half of their current valuations and you didn't know how to run either company, Exxon-Mobil would be worth many times more to you just from being able to liquidate the assets.
I realize the market cap is based on more than that but I guess I'm wondering why tangible assets don't play an even bigger role in valuations.
EDIT: AAPL doesn't have as much cash as I thought.