The Garden Igloo Kit. in a few different versions. could be a greenhouse +/or alternative to tent accommodations to house a few more summer retreatants. not particularly cost effective though, in my humble view.
Privacy fence finish // Shou sugi ban- Devised as a way to make wood less susceptible to fire and to keep away insects and rot, this longstanding Japanese method involves torching your building materials
As I grew, I would put plans that I felt safe and secure in changing to my taste, simply a bit, here and there. So why simply limitation yourself to developing furniture? Chairs are typically neglected woodworking tasks.