Staples offers free next business day shipping on orders over $50. They also have a 110% price match guarantee. I have used those features a few times now, and like it a lot. And now you can get discount coupons as well:

special-offers-from-staples (PDF; 288 kb)

Discounts not available in stores; savings only apply to online, phone or fax orders.

Coupon codes expire May 22, 2009 and apply to Staples Canada (