The ancient Chinese tile game of Mahjong is perfect for adapting to different themes throughout the year. This holiday-themed game of Mahjong is great for getting you in the spirit, or you can show your kids how to play. The object of the game is easy — just clear out matching tiles in pairs. In order to be able to be matched, the tiles have to be on the same “level,” but you don’t have to worry as much about that with an online version, since it simply won’t let you select a tile that cannot played. This web site has five different layouts to play, and if you get stuck, there’s a “hint” button too.