An NFT is a way for a collector of digital content to authenticate ownership of the work via blockchain technology, the same stuff used in Bitcoin and other cryptocurrency transactions. Pablo Rodriguez-Fraile, who sold that video for millions, compared it to the difference between owning the Mona Lisa and owning a picture of the Mona Lisa you took on your trip to Paris. “The reality here is that this is very, very valuable because of who is behind it,” he said.

The person behind the video is digital artist Beeple, whose offline name is Mike Winkelmann. And he’s no one-hit wonder. Another piece of his is being sold by the respected auction house Christies, the first time the house has sold a piece of digital art in its more than 250 years of conducting auctions. Bids for his collage of 5,000 digital images have reached over $3 million, and who knows how high it will go by the time the sale closes on March 11.

The NBA has also taken advantage of the rapidly growing market for NFTs, selling authenticated clips of basketball games on its Top Shot website. The site pulled in over $250 million in sales in its first five months of being online. One buyer paid the ridiculous price of $208,000 for a clip of LeBron James slam dunking, which in all likelihood could have been Googled for free.