Originally Posted by
planemechanic
I would imagine either the CIA/NSA or the US DOD has better super computers that they just don't talk about.
Doubtful; they have the budget to build a computer optimized for any given task, and wouldn't need a big general-purpose supercomputer. If they do, the DoE can sell them time.
For cracking encryption, getting an Application-Specific Integrated Circuit (ASIC) designed and built pays off if you're going to be buying them in volume. For other military tasks, there's going to be a requirement that they distribute them, and at that point you have to decide if it all has to be in the same building to count as a supercomputer or not. Facebook and Google certainly have more processing power, but they don't call the network spanning their datacenters a "supercomputer" for some reason.