On-line retail store services featuring digital collectibles that can be traded on the blockchain; On-line retail store services featuring sports game used memorabilia as digital collectibles; On-line retail store services featuring virtual goods, crypto-collectibles and non-fungible tokens on a blockchain network; Operating on-line marketplaces featuring digital collectibles, virtual goods, and non-fungible tokens; Operating on-line marketplaces for sellers and buyers of goods and/or services; Providing a website featuring an online marketplace for exchanging goods and services with other users; Provision of an on-line marketplace for buyers and sellers of digital collectibles that can be traded on the blockchain; Maintaining a registry of sports memorabilia and works of art; Marketing services, namely, promotional services for the memorabilia and collectables of others