CUCaTS
Puzzlehunt 2014
h(x) = 075f00fb383df7829e1f32e4d1c9d766bbaa8da75fe6aaa2e0cf421c443d43d3
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).