My very favorites are the Shoes-Which-Shall-Not-Be-Named

, but I do have some others that I like and have worn in the past.
-Clark's suede athletic-type sandals (although they are murder on the feet if they get wet)
-Birkenstock one band slides
-flip flops- the platform type (lots of cushioning between the pavement and my feet)
I just tried on some Adidas flips at Dick's Sporting Goods that I might have to get for WDW walking. They are fabric uppers, and there is some kind of gel in the sole that feels nice and squishy on your feet. They conform to the shape of your foot and are really cushy to walk around in.
I also want to get some Rainbow or Teva Mush flippies to try this fall.