Have just been exploring the NASA photo archives. More delights to come.
'Even bubbles are more interesting in space. Here, a water bubble floats freely on the International Space Station, showing an image of Expedition 10 Commander Leroy Chiao. Chiao's picture is upside down because light is refracted, or bent, as it passes from one medium to another -- in this case, air to water. The same effect produces rainbows when light passes through raindrops in the air.'