Watch a 2,000-voice choir sing “What a Wonderful World” in the Eaton Centre

Choir! Choir! Choir! needs no introduction. Millions of people around the world have watched the local singers’ triumphant choral arrangements of Leonard Cohen’s “Hallelujah” (with Rufus Wainwright in an abandoned power plant), Prince’s “When Doves Cry” (at Massey Hall) and David Bowie’s “Space Oddity” (at the AGO). Their latest feat: a massive singalong at Toronto’s Eaton Centre. The group sang Louis Armstrong’s “What a Wonderful World” to unveil the mall’s gargantuan Christmas tree and launch their own holiday campaign, #25DaysofCharity, through which they’ll donate $1,000 (or more) to 25 charities. If the video makes you want to join in the fun, Choir! sings nearly every Tuesday and Wednesday night at Clinton’s Tavern.