Vast.ai operates a marketplace connecting users with underutilized GPU capacity across cloud providers, offering substantial cost savings versus traditional clouds. The platform features an auction-style pricing model, real-time performance metrics, and flexible rental periods. Perfect for researchers and indie developers, it supports all major ML frameworks through pre-configured templates. Advanced filters help users find optimal hardware for specific workloads (CUDA cores, memory bandwidth etc.). Vast.ai's unique value proposition lies in its price transparency and community-driven supply network.