Why is information better than any other business? Because unlike other kinds of labor, by giving or selling you my information I am not losing anything... in fact we are both gaining something. That is the real sharing economy.

Just like a candle loses no fire by lighting another candle. 

How would Adam try the site? He's not a teacher! NYT says it's cool though...

I haven't tried the site but it looks like they have more than just teachers there.