As of my last knowledge update in January 2022, the decentralized finance (DeFi) space is dynamic, and new projects and developments may have emerged since then. Here are some notable decentralized exchange (DEX) aggregators that were recognized for their role in optimizing trading across various DEX platforms:

1. 1inch:

   • Key Features: 1inch offers users the ability to find and execute trades at the best prices across multiple DEXs. It aggregates liquidity from various sources, including Uniswap, SushiSwap, and others.

   • Advantages: Gas optimization, multi-chain support, and an intuitive interface.

2. ParaSwap:

   • Key Features: ParaSwap is known for finding the most efficient routes for token swaps across different DEXs, optimizing for both price and gas fees.

   • Advantages: Aggregates liquidity from various decentralized exchanges, offering competitive rates.

3. Matcha:

   • Key Features: Matcha is a user-friendly DEX aggregator built on top of the 0x protocol. It allows users to trade tokens at the best prices across various liquidity sources.

   • Advantages: Clean and simple interface, with access to 0x's liquidity network.

4. Dex.ag:

   • Key Features: Dex.ag is a decentralized exchange aggregator that scans multiple DEXs to provide users with the best possible trading rates.

   • Advantages: Aggregates liquidity from multiple sources, enabling users to trade across various platforms without the need for manual comparison.

5. Kyber Network:

   • Key Features: Kyber Network is a decentralized liquidity protocol that aggregates liquidity from various sources to provide users with the best token swap rates.

   • Advantages: On-chain liquidity aggregation, diverse token support, and integration with wallets and DApps.

6. 0x API:

   • Key Features: 0x API is a liquidity aggregator that allows developers to access aggregated liquidity from multiple DEXs in a decentralized manner.

   • Advantages: Designed for developers, it provides flexibility and customization options.

7. Balancer:

   • Key Features: Balancer is a decentralized automated portfolio manager and liquidity provider that allows users to trade and provide liquidity across multiple tokens.

   • Advantages: Liquidity pools with customizable weights, enabling dynamic trading and yield farming strategies.

8. Bancor:

   • Key Features: Bancor is a decentralized liquidity protocol that enables automated and decentralized token swaps. It uses an automated market maker (AMM) model.

   • Advantages: Continuous liquidity, low slippage, and protection against impermanent loss.

9. Mooniswap:

   • Key Features: Mooniswap is an automated liquidity protocol designed to reduce impermanent loss by utilizing a virtual price oracle.

   • Advantages: Focus on minimizing impermanent loss, competitive rates, and capital efficiency.

10. Uniswap (V3) with Optimism (OΞ):

    • Key Features: Uniswap is a decentralized automated market maker (AMM). Uniswap V3, when used with Layer 2 scaling solution Optimism, provides gas-efficient and low-cost trading.

    • Advantages: Lower gas fees and improved scalability with Layer 2 technology.

Before using any DEX aggregator, it's essential to conduct your own research, consider factors such as security, fees, supported tokens, and user experience. Additionally, check for the latest developments and new entrants in the DeFi space, as it evolves rapidly.