As a Ranger for The Dyrt, I get products to test from time to time. For the last two months I've been wearing the OOFOS OOahh Sport Slide Sandals and boy are they comfortable.
I started wearing them only at times they were mainly advertised and intended: A recovery sandal to wear after exercise (runners love these). I was wearing them after playing hockey, and as my post-hiking footwear.
They're fine in showers and are crazy cushiony because of their arch support and foam material. I wear them all the time now, just because I like the amount of impact absorption these puppies can handle, which saves some stress in my knees and back, and that's always good even when you don't have back problems like me. Get the Project Pink edition ones so $10 of your purchase goes towards breast cancer research. After 2 months of solid use logging around 100 miles over every realistic terrain (loose gavel, pavement, indoors, locker room showers, grass, backcountry campsites, etc. etc.) the tread is finally showing signs of wear down.
If they get smelly you can machine wash them (still haven't needed to) and the OOfoam has some moisture and bacteria resistant properties to keep the bad smells from sinking in. Get your feet a pair of these people, they're so light and comfortable.