This is my entry for the "Above the Clouds Skin Contest" because Valkries ride flying horses in the sky.

"The Valkyries are female warlike virgins, who mounts upon horses and arms themselves with helmets and spears. They          decides who will die in a battle. They will hover over the battlefield, like birds over their prey. There will be six, nine, or thirteen Valkyries at a time. They will select among half of those who dies in battle. And then bring them to Valhalla.

The other half will go to the goddess Freya’s afterlife field Folkvangr. Freya always has the first pick, of the fallen Vikings. Odin allows some of the maidens to take the form of beautiful white swans, but if a Valkyrie is seen by a human without her swanlike disguise, she will become an ordinary mortal and can never again return to Valhalla." source http://www.viking-mythology.com/valkyries.php

Valkyries ride flying horses as seen in this picture