There is a seemingly growing movement toward small homes. Many of their features are similar to boats, in terms of making the most use of space, etc.
Something I hadn’t ran into was small floating homes. Kind of an upscale, moored houseboat. I love the large picture windows.
Stephanie Reiley’s has a tiny floating home on the Columbia River outside of Portland, OR. She has a detailed blog at ComingUnmoored.com.