Ice Hotel in Kiruna, Sweden | For more top experiences, like this one, in Northern Sweden see here: http://www.lonelyplanet.com/sweden/norrland/kiruna/travel-tips-and-articles/top-winter-experiences-in-northern-sweden
Why not go all the way when planning your vacation in Iceland, and book some nights at an ice hotel? It is a unique experience to sleep in a room made of ice, and don't worry, you won't be cold. You are warmed up by hot drinks and reindeer fur. The decorations are beautiful, and the hotel are build up year after year. Imagine going to sleep there after a nice day in the snow, seeing northern lights, chilling in a hot tub and getting warm in a sauna. Just perfect for winter luxury.
Jukkasjarvi, Sweden: An 8 mile dog sled journey is one of the best ways to get to the Kuruna’s Ice Hotel - an ice castle built each year beginning in October using 10,000 tons of ice and 30,000 tons of snow.