Lately most voucher codes from Air France have been $50 or $60 but here is one a bit higher but it is only for premium economy bookings:
Receive $100 off of Premium Voyageur (premium economy) flight reservations over $1000 departing from Montreal, Toronto and Ottawa to any Air France destination that offers a Premium Voyageur fare. Use promo code AFFPV891. Travel must be between December 1st 2010 and April 30th, 2011 with the latest return being August 31st, 2011.
Book online at Air France