Water is abundant. Plenty of it on this planet. Should be extremely cheap... if you think of "water in general".

But start to divide it based on what composition it has, where it is, how much it costs to transform quality Q1 water to quality Q5 water and so on. Then you can get to placing bets on wheter there will be enough water at place P1 and time T1 etc. Then, at the consumer level, you have bottled water with different packaging, aesthetic values and trustworthiness associated with it etc.

And you can suddenly sell 0.5l of water for $10 even if the planet is full of it :)

I imagine one day we'll have the same for "ideas", but more complex. We'll have "idea casinos" betting on implementation successes of various ideas. Meta-casinos betting on the casinos net profit. Derivatives-of-derivatives-of-derivates... if you want to use stock-market terms ...you get the point.

Things can be cheap in a "country-side market" based purely on selling things "mixed up", unsorted and unrated. Attach ratings and bets and estimates to them and... it's a whole new an much cooler game to play :)