1. What is Starknet?

StarkNet is the strategic product of Starkware to conquer the L2 market share. After releasing the Alpha version, many crypto builders have been on board the platform and joined hands in developing startups.
Numbers of projects on StarkNet:

DeFi: 13 projects;
Game & NFTs: 12 projects;
Wallets: Ledger, Argent, and WalletConnect;
Tools: Warp, Nethermind, Token Flow, and Equilibrium;
Others: Snapshot, Yagi, and Zorro;

2. Infrastructure

Celer Network (token: CELR) is a layer-2 scaling platform that ensures mass adoption of blockchain applications on Ethereum, Polkadot, and other blockchains.
Immutable X (toke: IMX) is a blockchain platform that simplifies the creation of non-fungible token (NFT) projects for developers. The protocol aims to achieve security and scalability for the network without compromising on either of them.
Nethermind has a world class team of builders and researchers with expertise in Ethereum, protocol engineering, layer 2 scaling, decentralized finance, smart contracts development and enterprise blockchain
Equilibrium is an interesting decentralized finance project (DeFi) created in the blockchain of EOS, with the aim of creating a high-speed, low-cost and easily accessible DeFi and DEX cross-chain system.
OpenZeppelin is an open-source framework to build secure smart contracts. OpenZeppelin provides a complete suite of security products and audit services to build, manage, and inspect all aspects of software development and operations for decentralized applications
Figment’s development platform, DataHub, allows developers and entrepreneurs to use the most powerful and unique features of a blockchain without having to become protocol experts.
Briq: Provides an NFT build tool with a basic elements-based NFT fabrication and synthesis system called briq. Briqs can be combined to create more complex structures called aggregates.
Empiric: Provide infrastructure for data

3. Trading multichain platform

rhino.fi, formerly DeversiFi, is a multi-chain, self-custodial DeFi platform hosted on layer 2, on top of the Ethereum blockchain.
dYdX is a decentralized exchange built on the Ethereum network delivering key financial instruments to users such as perpetuals, margin and spot trading, as well as lending and borrowing.
MES Protocol is a highly scalable and performant orderbook DEX that offers user experience similar to traditional exchanges, but fully decentralized and permissionless.
Zigzag Exchange is a decentralized exchange focused purely on being powered by ZK technology.

4. Wallet

Argent (no token yet)
Ledger (no token yet)

5. Defi

ZkLend is an L2 money-market protocol built on StarkNet, combining zk-rollup scalability, superior transaction speed, and cost-savings with Ethereum's security.
Hashstack finance is a decentralized financial network that provides multi-chain interoperable complex blockchain applications and protocols to offers under-collateralized loans.