CUCaTS
Puzzlehunt 2014
h(x) = 0b872e2240c5d9078463bd84ede021cb1d5fe82f47e667216aba96c8bfaeb9ce
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).