Snapfish Canada: 20 Free Prints (Postage not included)
Register at Snapfish.ca and receive 20 free prints upon the first time you upload your prints. The prints you will receive are 4 x 6. Evidently this doesn't include postage, but you could probably get them sent with whatever you are ordering.
Evidently you can get prints for as low as $0.12 a piece (pre-paid) and from forums I have read that Snapfish often has good promo codes.
I have unfortunately not tested this as I have had slight issues with uploading my photos to the web. If a Mooser would be so kind as to test this and comment that would be great.