Ethereum dApp ideas?


I was wondering how many websites are taking advantage of the login with Metamask idea?

Like for example:

  1. Buy an NFT collection, login with metamask, and get access to premium content for NFT holders
  2. Recreate Substack but must have NFT holding or token holding to access.
  3. Recreate Twitter but verify holdings of an NFT or $$$ amount of crypto. (can act as chrome extension that sits on crypto)

Basically, authenticating yourself as the owner of a wallet, linking it to a centralized account to access to something or to validate your identity as the holder of the wallet.

Have these ideas already been tried?