I like looking at market caps.
For instance, lately, I've been following Facebook's market cap.
Market seems to suggest that Facebook and Berkshire Hathaway have approximately the same value, at least in market cap. In other words, if you wanted to swap all of Berkshire's future earnings for all of Facebook's future earnings, it'd be a fair trade.
I understand serious people invest in Facebook, but I just can't take the above seriously. It makes me laugh every time I think of it.