As you may see in the Tapioca The thread, I ate at the szechuan hole-in-the-wall last night and loved every bit of it (only question is when we're returning...)
Killing time before meeting friends there, we rambled a bit on St. Catherine and spotted "BUNS", a very narrow space between St. Mathieu and St. Marc.
We stopped in after Tapioca to help out the young entrepreneurs as well as procure perhaps a late night snack.
They have a 48" BBQ which is in the window showcase and offer hamburgers and grilled potatoes - thats it.
Burgers are served on what looks like custom-made buns (they come out of a box and cut them to order) which are toasted on the grill. $4 and include cheese which looks like hand cut mozzarella.
Potatoes are par-cooked (I think in the microwave) to al dante then seasoned and grilled up on a griddle which sits on the grill.
I'm not savvy on the burger scene in MTL, but I hope these guys do well. They have a very simple idea and the burgers, perhaps not an epiphany, make good late night snacks.