Decor and furniture
Sign Decal Wood 4x4
It's a sign. You write things on it.
Harvest drops
Wood× 2
Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.
When it collapses
Falling, it leaves 
Wood Debris (Terrain) (75% of the time) where it lands.
Where to find (4 POIs)
Diamond's Mens Club (tier 4), HSP Logistics (tier 4), 3rd Eye Optometry, Ship-n-sip Station.
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.