German furniture designer Lennart Ebert, who is also a trained Schreiner (Joiner), designed this stunningly simple and beautiful T3 Trestle:

"T3 is a minimalist draft with an economic manufacturing process and distribution at the center of the design. In its production with 5-axis tube laser technology, only semi-finished profiles are used. The central design element of T3 is the striking T-profile, which shapes the support for the tabletop and the legs. these are made of round tube that is resistant to bending. Because of its low weight and flexibility due to dismountability, T3 is particularly well-suited for a flexible living and working environment."

I would guess that these are actually pretty stable, despite their narrow splay.