I've definitely wondered about SHA-256 encryption and its origins.  I was having a conversation with a gentlemen, sharing with him a little about bitcoin when he somehow brought up encryption levels and he said he was into that stuff, asked if bitcoin was 128 or what and I said no I believe it's 256, he looked in disbelief at me and said that requires national security level clearance, that can't be right.  I then googled it, confirmed SHA 256 and he looked even more stunned.  He then said, "that is interesting and I'll have to look more into it when I get home."

If I had not had a conversation with my friend about the origin of the SHA 256 algorithm coming from NSA patents, I wouldn't have felt quite the same little tingle in my spine when I had this conversation with someone whom had never heard of a bitcoin, prior to the 270 price bubble.  Since I had, and being a naturally inquisitive historian, this has definitely been an interesting thought, especially since 256 may be pretty well surpassed with petaflop computing already.  Think about the craziest largest array of bitcoin miners you've ever seen, multiply that by 100 and think about 100 locations running that kind of power...I'm pretty sure 256 could be cracked if you have enough resources, and if we're not already there, Moore's law would suggest they are starting manufacture of the technology that will run it soon.  I'm pretty sure Military grade encryption is already beyond 256...suggesting they don't find it secure enough.

Consider this:
http://www.techspot.com/news/51044-25-gpu-cluster-can-brute-force-windows-password-in-record-time.html