CUCaTS
Puzzlehunt 2014
h(x) = 80a1e9752666ce7472547f24e2de9c0f0b28e006153e1dd748464886b2010ab7
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).