An avid follower of ice hockey, he has been a fan of the Toronto Maple Leafs since his childhood in the Leaside and Etobicoke communities in Toronto. Harper is also a fan of the Calgary Flames. He published a book, "" (2013), which chronicles the growth of professional hockey, particularly in Toronto, and writes articles occasionally on the subject. Harper appeared on The Sports Network (TSN) during the broadcast of the Canada–Russia final of the 2007 World Junior Ice Hockey Championships. He was interviewed and expressed his views on the state of hockey and his preference for an overtime period in lieu of a shoot-out. In February 2010, Harper interviewed former National Hockey League greats Wayne Gretzky and Gordie Howe for a Saskatoon Kinsmen Club charity event.