To the untrained observer, one video clip showed NBA superstar LeBron James in one of his more spectacular moves; but it lasted no more than a few dozen seconds. On Top Shot, however, it instantly became a collector's item that sold on Monday for an eye-popping $208,000.

The video sequence is an "NFT" -- a Non-Fungible Token -- a virtual object whose identity, authenticity and traceability are theoretically indisputable and tamper-proof, thanks to the same "blockchain" technology used to ensure the security of cryptocurrencies like the hugely popular bitcoin.

Launched in early October by Canadian firm Dapper Labs in partnership with the National Basketball Association, Top Shot allows customers to buy and sell these short video clips -- called "moments" -- at prices that vary depending on demand and rarity.