Balancer

Balancer differs from a regular AMM in that a pool is not limited to a pair of tokens in equal shares. It can hold up to eight assets with arbitrary weights, say 80% of one token and 20% of another. Such a pool behaves like a portfolio. It rebalances itself: when prices move, arbitrage pulls the weights back to target, and the owner does nothing by hand.

For a liquidity provider this is a way to hold a chosen portfolio mix and collect fees from swaps inside it. The protocol runs on six networks including Ethereum, Arbitrum, Polygon, Base and Gnosis. Pool setup is complex, so for a simple swap general-purpose exchanges are easier.