Cryptocurrency fans may have gotten more than they bargained for when the president and his wife launched a pair of tokens last week.

Just days ahead of his return to the White House, President Trump and his wife, Melania, launched a pair of meme coins that have skyrocketed in value and earned them billions of dollars, at least on paper.

But the launch of the so-called meme-coin - a cryptocurrency with no utility other than for fun or speculation - has been widely criticised by industry insiders. "Trump's comments about not knowing much about the coin back up my opinion that he is making a mockery of the industry. It's a stunt," says Danny Scott, CEO of CoinCorner.