This wedging table can be constructed for less than $100 in parts from Home Depot. If you are building one, make sure you start in the garden department. You'll need a "smooth" 2x2 concrete paving stone/slab.
«I need to be alone. I need to ponder my shame and my despair in seclusion; I need the sunshine and the paving stones of the streets without companions, without conversation, face to face with myself, with only the music of my heart for company». —Henry Miller, Tropic of Cancer