Exploring the streets of Thailand (especially Bangkok), you’ll often come upon shops or massage parlors that have a fish tank containing dozens and dozens of tiny fish. These tanks are not for decoration. They are the fish doctors and they will take care of your feet.
The concept is quite simple. You wash your feet and simply dunk them in the tank. The fish will do the rest. They will gather around your feet and simply feed of your dead skin. The process is totally painless but you will get the same tingly sensation as when one of your limbs gets its blood circulation cut off.
The whole experience lasts a few minutes and is quite cheap. I honestly did not see any difference in the general appearance/feel of my feet afterwards but is was quite fun to try.