Stake DAO created a liquid locker for the CRV token, the governance token of Curve, called sdCRV. As sdCRV is a liquid form of veCRV, users have the possibility to deposit and stake directly on Stake DAO or buy on the secondary market, using the sdCRV/CRV pool.
TL;DR: Liquid Lockers unlock the following from lockable tokens:
Maximised yield
Exit liquidity (convert back to underlying governance token)
Governance power (no vote-lock)
Bribing (sell your votes)
Cross-chain accessibility (to come)
Boost your voting power (using veSDT)
What are Liquid Lockers ?
Stake DAO Liquid Lockers allow DeFi users to unlock power from lockable tokens (e.g. ANGLE, FXS, CRV) without having to compromise on yield, voting power, or liquidity.
With Stake DAO Liquid Lockers, anyone that supplies assets receives the maximum yield boost while retaining full voting rights and benefits of their token's native protocol, as well as the ability to boost voting rights, on-sell them, and exit their position back to the underlying token.