Decentralized networks are a rare medium well-done. We present the Steak Network, a decentralized social network of Steak enthusiasts built on top of Ethereum. The core feature of the Steak Network is the Steakchain, a set of validated, user-submitted Proofs of Steak. The network defends itself against malicious attacks using Proof of Steak, a novel protocol capable of securing a blockchain given proofs that cannot be computed cryptographically, backed by TrueBit and a Proof of Stake protocol. Using the Steak Network, users can trustlessly share Proof of Steak, knowing for certain that the Steakchain is exclusively made up of verifiably rare (or medium-rare) pictures of steak. Yes, I did all of this for the joke "Proof of Steak". But it turns out you could probably use Proof of Steak (this registry-curation protocol) to secure any list where the membership proofs ("I belong in this list of things") can't be modeled cryptographically, primarily things that are crowd-opinion-based or aren't yet machine-verifiable. It's effectively a Token-Curated Registry protocol implementation, but with the addition of Forced errors to incentivise verifiers. It could be used to create a set of verifiably rare memes, for example, or decentrally curate high-quality datasets for machine learning or AI training, or even creating a decentralized MTurk. Proof of Steak could be applied in any case where a high-quality list of items is more valuable than the sum of its parts.