Stück Natur: The Microenvironment-in-a-Jar by Hans-Rucker & Co. This is a museum piece, but looks easy to duplicate with a miniature house or shed, soil, and moss in a covered glass jar - very charming!
Its so easy to create your own Christmas terrarium. Just take a Mason jar, fill it with snow and add a Christmas tree and a reindeer for a DIY Christmas scene that will last forever. Change up the reindeer to a Santa for a different look.