What is "rt!"

Randall Thorne, better known by his pseudonym RT!, is a Canadian filmmaker of Trinidadian and Barbadian heritage. Thorne is noted for "manufacturing deeply immersive visual worlds" and is the most awarded music video director in Canada,[1] having received seventeen international awards over ten years in the field of music video. He is the co-owner and Executive Director of the NE Creative Group, in addition to holding a position on its roster of directors. He is also a director with the non-profit cultural organization, The Remix Project.