The directory.io thing is really interesting. I assume the idea is that the site does the calculation in some way that in theory produces a full set of results and they hope that Google will index more and more of them over time, thus allowing a search for some public keys to find the corresponding private key. It seems like Google does index a few pages (including some higher number ones), but not too many.
Edit2: This is one of those basic security things I have trouble getting an intuitive grasp of (but need to). How much can being able to determine a random small part of a random large key space hurt? I've worried about this before with 256-bit key spaces and been reassured with calculations, but I still don't intuitively get it.
It's not interesting really, it just takes the page number and generates the keys for that particular page on the fly. Google will most certainly never find anything, if nothing else the CPU of the server is a severe bottleneck when you're talking about 2^160 keys. You could load pages on that webserver until the sun becomes a red giant and consumes the earth, and you wouldn't have covered even the smallest percentage of the keyspace.
Edit: redit threads: http://www.reddit.com/r/Bitcoin/comments/1rua34/all_bitcoin_... http://www.reddit.com/r/Bitcoin/comments/1ruk0z/dont_panic_d...
Edit2: This is one of those basic security things I have trouble getting an intuitive grasp of (but need to). How much can being able to determine a random small part of a random large key space hurt? I've worried about this before with 256-bit key spaces and been reassured with calculations, but I still don't intuitively get it.