Notable: The owners of this brown shingled home perched on a Mill Valley hillside say it feels like a tree house albeit one with three levels, a wine cellar and a "Harry Potter" room under the stairs where their daughter once liked to hide.

WSJ: For $1.05 Million, a Spot on a Mill Valley Hillside

The architect created a tree house-like design, where two floors of living space floated above ground, anchored by a steel support.

WSJ: Tiny New House, Old Kyoto Soul