CUCaTS
Puzzlehunt 2014
h(x) = 4fc156e543aa5886d8b6db8d1a7f6654edcd6f39f9689cc634cbd3471c35824a
author: unknown
h(x) looks like a cryptographic hash, and refreshing the page shows it changes every 5s. We find that the SHA256 hash of the unix time (floored by 5 seconds) gives us the same hash. Thus the answer is the current unix time (and values within ± a minute are accepted).