The electric-truck maker might be an interesting play for speculative investors.Nikola (NKLA -2.67%), a producer of electric semi trucks, saw its market cap hit $28.8 billion as its stock hit its record high of $79.73 on June 9, 2020. But at the time of this writing, it trades at about $0.56 a share with a market cap of $750 million.The stock collapsed after the company missed its own production estimates; its founder and former CEO, Trevor Milton, was convicted of securities and wire fraud; and it recalled ...