SolnadoCash is a platform within the Solana ecosystem focusing on user anonymity and fund safety. It uses Monero to ensure privacy by enabling users to deposit and withdraw cryptocurrency in a way that makes transactions difficult to trace. The protocol works by having users deposit funds with a secret hash to a pool, and withdrawals are made without linking back to the deposit, thereby preserving transaction anonymity and breaking the link between deposit and withdrawal, enhancing privacy against external observation.