Bitcoins cost of production are about $1
1.5$ - 2$
You forget the extras needed for production, on small scale or large scale bitcoin mining.
Even at $2 cost of production the price of bitcoins has overshot any sense of reality.
Even with a couple of months worth of increased difficulty built into the current price it's current price is a bubble.
What are the barriers to entry a $700 -$1000 machine.
It takes very little knowledge to start mining for bitcoins.
This will end very badly for anyone who has invested in bitcoins in the last 30 days
How long until a bubble is not a bubble anymore? When you start calling it dolar?