so... if we aimed all the Hashing power of the Bitcoin network on one address it would take 500 million years? Hey man It's only a matter of time before insane quantum computers just start cracking the codes by the second. I can imagine this will happen one day, when the Bitcoin network migrates to a new protocol based on quantum security. Those computers will tear Bitcoin apart when they finally are able to produce them in mass, and start migrating all the accounts to a new system like a block reward, Or just like the free market migrate by choice to something safer.