You can use Adobe Photoshop's displacement maps to create refraction effects, such as the view through water droplets. And once you've created the water and the displacement map, you can swap out the background and replace it with other images!
Using a mixture of simple techniques, we are going to blend 2 different elements to a face. By adding minor details like Icicles and Melting Plastics, we are able to portray an extreme freezing effect on one side, and give a blazing hot effect to the other.