American Express Aeroplan Plus Platinum Card 50,000 Sign-up Bonus
Air Canada's frequent flyer program, Aeroplan (which is actually a separate company from the airline), has some good awards, especially the 80,000 point business class from North America to most parts of central/Western Europe. They also have a competitive card sign-up bonus going on right now for their co-branded American Express Aeroplan Plus Platinum card: 50,000 points (25,000 with first purchase and 25,000 after $1,000 spend in first three months). Simply sign-up through the link and use promo code 50100. While the card comes with a hefty $499 annual fee, you can cancel it after hitting your spend to get a prorated rebate on your annual fee. If you want to keep your card, the benefits may pay for themselves. If you already have an American Express Platinum card, some people have had luck convincing Amex to let them keep both cards for one $499 annual fee. This may depend on your history with Amex, but it can't hurt to ask if you already have a Platinum card.
1.25 miles per dollar spent on first $25,000 in spend
1 mile per dollar after $25,000 in spend
2 for 1 shorthaul 15,000 mile redemption
Access to the Maple Leaf Lounge
Free Priority Pass Membership ($27 access to hundreds of international lounges)
Free Hertz Gold (one class upgrades)
Fairmont Platinum after 5 stays (link)
If you aren't into the $499 annual fee, you can still getthe Aeroplan Plus Gold Card for $120/year.
Note: these are charge cards, so the balance must be paid off each month, or else you pay a steep 30% annual interest on your carried balance (which would easily negate the value of points received).