

Bitcoin Lorem Ipsum - zaroth
https://blockchain.info/tx/57bfd63000bbfa6e9a61f7285a4abf9aef91dfcfba4fe0f940b431653eb8068b

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zaroth
These 'vanity' addresses are generated using brute force. Randomly generate a
private key, calculate the corresponding public key, convert the public key
into the standard Bitcoin format, and then check if the pattern matches.

There's a nice program called 'vanitygen' which is has been highly optimized
for this purpose. On a CPU it can test 250-500k addresses per second. Not sure
about the GPU performance, but there's an OpenCL version as well. The code is
on GitHub (<https://github.com/samr7/vanitygen>) and quite easy to read if
you're interested in how it all works underneath.

The difficulty of finding your desired vanity address increases exponentially
with the length of the string you want to appear. That's what makes some of
these addresses so impressive, for example:

    
    
       11PraesentNonEratPurusNonXXc9VAcD
    

vanitygen is telling me I have a 50% chance of generating an address that
starts with '11PraesentNonEratPurusNon' in 5e30 years (at 250k/sec). Someone
put a very impressive amount of compute into that one little transaction!

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zaroth
I guess the other possibility is they picked the addresses strings directly,
to look like valid addresses, but don't actually possess the corresponding
private keys!

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L0j1k
This is incredibly impressive. Someone dedicated a very powerful mining rig
(presumably) to this task for a not insignificant amount of time.

