Just did a quick sear on kijiji (no it's not me selling). Some guy is selling 8 passes for $50/ticket. Might be worth picking up as you can use on multiple hills.
http://calgary.kijiji.ca/c-buy-and-s...AdIdZ243195183
If you switch your venue to Louise/Kicking Horse/Castle Mountain, the 2010/11 Louise card is $100, which comes with 2 lift tickets and $50/ticket thereafter.
http://www.skilouise.com/louise_cards.php
Never been to Castle, but heard you can get pretty good deals on weekend packages where you ski and stay on the hill. Might be worth checking out.