Grey Cup halftime showRead full article1 / 4Grey CupJustin Bieber performs during the half-time show at the 100th CFL Grey Cup game between the Toronto Argonauts and teh Calgary Stampeders Sunday November 25, 2012 in Toronto. THE CANADIAN PRESS/Sean KilpatrickSean KilpatrickGordon Lightfoot, Marianas Trench, Carly Rae Jepson and Justin Bieber all performed at the 100th Grey Cup.