This document proposes ThriftyPaxos, a state machine replication protocol that provides cheap and available replication through two techniques: (1) on-demand instantiation that activates backup replicas only when needed, and (2) lazy recovery that performs state transfer in the background without halting the system. The evaluation shows that ThriftyPaxos reduces replication costs compared to standard Paxos, and maintains availability during state transfers unlike CheapBFT, making it suitable for large-scale systems.