BMV is a great place for cheap books. Sometimes I love the "new book" smell, and sometimes I want a cheap book that has been loved. BMV is where you come for the latter.
I took a bunch of English courses in university and bought a bunch of my novels from here so I didn't have to spend $30 per book at the Ryerson bookstore. They've got most of the classics, as well as a bunch of rare gems that you'll find if you look for long enough.
It's a tiny place, but it also makes it more manageable. A good place to browse, but head over to the Bloor location if you're searching for something specific.