Try going for coffee downtown early on a Sunday morning. Place after place is closed because downtown isn't actually the place to be in Calgary on a Sunday morning. Except Caffe Artigiano. Not only is it one of a few places to go, but it's also a good place to go.
Plenty of seating, friendly staff, yummy lattes and tasty treats, Caffe Artigiano offered an excellent place to sit down and catch up with friends.
A thanks to Geoff B's note that the entrance faces onto 3rd Street. I might've had a bit of trouble spotting it otherwise.