I used the snow globe idea for a Christmas CD cover this year, and re-worked the idea for our Christmas card. All of the elements were shot separately - the kids playing in the fake snow, the snow globe, and Harry the dog - and scanned into Photoshop. I erased everything inside the snow globe except for a few reflections around the edges. The base was resized so that it didn't dominate the picture, and I added more snow around the kids' feet and floating around them. Once all the elements were in place, I applied several different filters and lighting glare effects.