Policy on eBay.ca:
http://pages.ebay.ca/help/sell/bin.html
"Note: The minimum amount for which you can list an item is determined by eBay and varies by country"
Policy on .com:
http://pages.ebay.com/help/sell/bin.html
in fixed price format: http://pages.ebay.com/help/sell/fixed_price.html
in auction format:
http://pages.ebay.com/help/sell/f-auction.html
The fee table on .com:
http://pages.ebay.com/help/sell/fees.html
"**Fixed Price listings and the Buy it Now feature have a minimum price of $1.00. Multiple Item Auction (Dutch Auction) listings have a minimum price of $0.99."
on .ca:
http://pages.ebay.ca/help/sell/fees.html
"**Fixed-price items or items sold with Buy It Now have a minimum price of $1.00."
Why the difference between .ca and .com? I do not know.
.