I've done some searching, and the answer isn't completely apparent.

I'm flying in to YYC from ORD. I'll have no checked bags--carry on only. My flight is on a Saturday, so I wouldn't expect any major traffic. I'm landing mid-afternoon, so I have no idea what customs might be like.

Obviously there are variances in any estimate, but how long does it take:

1. To clear customs with a US passport?
2. To take the bus/C-train combo to the center?
3. Take a taxi/rental car to the center? Also, about what sort of cost should I expect on this option?

Are there other options between airport and downtown besides these two that I'm not considering?