We've made a zero-knowledge proof protocol for graph 3-coloring. Here are prover (52.86.232.163:32795) and verifier (52.86.232.163:32794) servers. Convince the verifier that you know the prover's graph-coloring! https://s3.amazonaws.com/bostonkeyparty/2016/48cdc8756b6a9a5052c6da2d061b9bd61d13a1fa.tgz