For block 12344:
20:58:10
signmessage APLLrWbHapoRVxLAxBUkDU1hkx4VbCJHQX "Koooooj owns this address"
20:58:10
IBBD3qd/bbh5npcj7pEQCBqZUwiYaaE/y097+P0EBeB5fH4eJCqvNzrxzm20P6kWFq/0wmp0cZQTHk78cpfaYbM=
For block 17302:
21:00:27
signmessage AbrPM2J3WLvgz87t13wU46VwvVW5dM1Vdq "Koooooj owns this address"
21:00:27
IH8dQ+I2e4WWZIpXbqhXrquLXMnNdx847+HUeuadcqyeB77XPe3tmN2bG/FdOPZv7id9Q0eMuQ4UO7iBaq0wUf0=
I think I got the right blocks and signed correctly; my local QT client returns true upon verification requests.
All of that verifies for me.
Primecoin's has both.
I find it a bit disappointing that for all of the extreme amounts of computational power that goes into Bitcoin's blockchain, all we get is a verification of the latest block. There's no interesting analysis possible of the proof-of-work statements. Primecoin at least doubles as an enormously huge chain of mildly interesting computations.
quick, lets make UFO coin. every signal decrypted and processed is a block. first person who decrypts it a processes is rewarded the block. now we have another scientific coin. see where i'm going with this? you know, at first i was being facetious but you just might have sold me. maybe scientific computations offered by prime and any future coins like it could offer a pseudo-backing for the currency, much in the way that physical gold and silver once backed physical paper money
Doing analysis of external datasets would be a bit difficult to accomplish in a decentralized cryptocurrency, and the work has to be extremely quick to verify that it's correct, so many types of computations are out of reach sadly.