Offering actual airline rewards? None.

Here are all the US$ cards currently issued in Canada:

• TD US$ Visa
• RBC US$ Visa
• BMO US$ Mastercard
• CIBC US$ Visa

In addition, BMO, RBC, TD and Desjardins have subsidiaries in the US. I know that both BMO (Harris Bank) and RBC will open accounts for Canadians without all the usual necessary documents or residency required for US accounts. I have heard, but cannot confirm, that both TD Bank (US) and Desjardins (US) will do so as well. Of these, I know Harris let's you do all of it online, whereas RBC requires you to go in person to a branch in Canada.

edit: Oh yeah, RBC is the only one that gives you seamless integration in online banking between your Canadian and US cards and accounts. All the others tend to be a little more bureaucratic in how things work.