CUCaTS
Puzzlehunt 2014
h(x) = f635a0cf4e7fdaa708baf933352374eeaf5ef22c8b6996cac0d99d496690f8e8
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).