In the spirit of today’s celebration of guitar gods and the people who love them, here’s a clip of six-string wonder J Mascis — who has already proven his skills at Guitar Hero — joining up with a dozen-plus excited Canadian indie rockers for a joyous impromptu post-show jam session in Toronto. It’s a “sixty-two beers” fueled rendition of “Backed Out On The …,” a track from Broken Social Scene co-founder Kevin Drew’s upcoming Spirit If album.