Billy Bishop Toronto City Airport (YTZ) is still my favorite. Landed on a beautiful summer afternoon, took the underground moving walkway to the mainland, then walked to our hotel. It was a weekend stay to catch a couple of ball games, so we packed light (backpacks), and walked from the hotel to the Rogers Centre for the Sunday afternoon tilt, then walked from Rogers Centre back to Billy Bishop for our flight back to IAD.
There's a free Porter shuttle bus that takes you from YTZ to the Royal York, but it's a pleasant walk in nice weather. Either way, it doesn't cost you a nickel.