Here are two customs I created for another contest, both winter-themed. My area had about 8 inches of snow on the first day of spring!
The Hoth ski patrol! Believe it or not, there is a little down time on Hoth, and for those troopers who get lost or injured while exploring, it's the ski patrol to the rescue! I used the TVC Hoth Luke head on a Hoth rebel trooper body. The skis, poles and snowshoes are from Gi Joe's Snow Job.
And a long-range recon patrol on tauntaun. These troopers are out for extended periods of time patrolling Hoth's frozen wastelands. It's the basic Hoth Rebel trooper accessorized with Commander Faie's smock and hood so he can better blend in with the environment. A pair of macrobinoculars are slung across his torso.
For both figures, I laid a paper plate on top of the snow so the figs wouldn't sink down.