This was the outfit I wore last year for Christmas. (The greens seem pretty clashy in the pic, but that is just from the flash. In person, the greens of the tights with the dress go nicely.) Very comfortable dress and tights!
Cardigan: $0 (came included with dress bought at WalMart.)
Dress: $15 (sale) Body Central
Tights: $11 Boston Store
Boots: $20 UrbanOg
(Last year. Notice the green colors...)