I found a great iPhone Application that I just have to share with you all. It comes from a fellow Canadian so you know that it has to be good.
The App is called “Simply Declare” http://www.simplydeclare.com/ and what it does is keep track of your purchases, automatically applies the correct currency conversion, lets you know at a glance how close you are to your Duty Free limit and finally, allows you to take a picture of your store receipt just in case the “man” wants proof of how much an item cost. Even they can’t believe how much cheaper things are in the U.S.!
The icing on the cake is that once all the items are entered you can email them to yourself in a pdf. This is great if you want to do some comparative shopping back home or you can’t remember where you got that great deal on the blue jeans or detergent for the next time you head over the border.