Keith Gill, known online as Roaring Kitty, streams live on YouTube for the first time in nearly four years, discussing his massive bet on the brick-and-mortar video game retailer GameStop.

Fast Money Halftime ReportCNBCbusiness newsfinance stockstock marketnews channelnews stationbreaking newsus newsworld newscablecable newsfinance newsmoneymoney tipsfinancial newsstock market newsstocks