Some popular DeFi projects and platforms include:

1. Uniswap
2. Compound
3. MakerDAO
4. Aave
5. SushiSwap
6. Yearn.Finance
7. Synthetix
8. Curve Finance
9. Balancer
10. Bancor
Decentralized Finance (DeFi) has gained significant traction in the blockchain and cryptocurrency space in recent years. There are a number of popular DeFi projects and platforms that have emerged, offering a range of financial services and products. Here are some of the most notable ones:

1. Uniswap - Uniswap is a decentralized exchange (DEX) that allows users to trade a variety of ERC-20 tokens directly from their wallets. It uses an automated market maker (AMM) system to facilitate trades, making it a popular choice for decentralized trading.

2. Compound - Compound is a decentralized lending platform that allows users to borrow and lend various cryptocurrencies. Users can earn interest on their deposited assets, or borrow them at competitive rates. Compound has quickly become one of the most popular DeFi lending platforms.

3. Aave - Aave is another decentralized lending platform that allows users to earn interest on their cryptocurrencies by supplying liquidity to the platform. Users can also borrow assets against their deposits, with the interest rates determined by supply and demand dynamics.

4. MakerDAO - MakerDAO is a decentralized autonomous organization (DAO) that governs the stablecoin DAI. Users can deposit collateral assets such as Ether (ETH) to generate DAI, which is pegged to the US dollar. MakerDAO has played a pivotal role in the DeFi ecosystem by offering a decentralized stablecoin.

5. Yearn.finance - Yearn.finance is a DeFi platform that automates yield farming strategies for users. It aggregates various DeFi protocols to optimize returns and minimize risks for users looking to maximize their yields in the DeFi space.

There are many other popular DeFi projects and platforms in the ecosystem, each offering unique features and services to cater to different needs and preferences. As the DeFi space continues to evolve and grow, it is important for users to conduct their own research and due diligence before participating in any DeFi project or platform. With proper understanding and caution, users can take advantage of the innovative opportunities that DeFi has to offer.