Public Goods: Wikipedia

One public good we all use is Wikipedia, the Free Encyclopedia. It's free, and you using it doesn't stop me from using it. 

How much benefit do we get from Wikipedia? This is hard to measure because using it is free. In 2013, Jonathan Band and Jonathan Gerafi tried to estimate the value that Wikipedia produces in a fun (but not very rigorous) paper. They estimated that Wikipedia created somewhere between 16.9 billion and $360 billion in value in 2013.* That means that Wikipedia produced more value than Iceland, and may have produced more value that Denmark in 2013. If we go with the author's reasonable midpoint estimate of $80 billion, then Wikipedia produced more value than Cuba did.  Wikipedia has only grown since then.

* One insane method they use estimates that Wikipedia creates more than $1 trillion in revenue, but I'm not including that here.