http://en.wikipedia.org/wiki/NIST_hash_function_competition#EntrantsI suggest we create a series of cryptocurrencies based on different hashes. Why? Because any one of them can be hacked including SHA256 and ECSDA. If we have a cryptocoin for every feasibly-survivable hash function out there, we can always have a cryptocurrency to rely on because at least one should survive for the next century or so. They could all be merge-mined together, creating the ultimate octopod of economic decentralization!
The best hash functions are the ones so good that the NISPT wouldn't want the general public having them. Look at the rejected entrants list of their competition for clues! Some of them the public doesn't even know about!
Personally, I think cryptocurrency can do much better than the NSA-created SHA256.