List of Unsolved Problems in Econ:
What happens when central bankers run out of ammo and realize monetary policy may not be an ideal path to fiscal stimulus? Or having the bright idea of devaluing your currency to depreciate your outstanding liabilities results in a mutually assured destruction scenario when every sovereign on earth implements the same idea simultaneously? And when "too-big-to-fail" entities amass derivative exposure that is 100X global GDP does it become time to panic yet?
But still its innovations like ZeroCoin and SmartContracts that give one hope that out of the rubble, creative solutions will arise. As long as they are grounded in economic reality and not fantasy, humanity will abide...
One thing that I think is missing from that list is how to factor in technology into economic models or measurements like GDP.
Right now this dark horse which in my view have the biggest single impact on our world is mostly left out as an externality which if you think about it is not just absurd but straight out irresponsible.
Politicians listen to economists and their models and as long as it's kept out of those models they can't react politically to it. And thus technology will keep moving faster than legislation.