Here are several websites, projects, and platforms similar in spirit to orb.blue, organized by theme:
Experimental Web Spaces & Archives
are.na
A collaborative platform for building collections of ideas. Many creators use it for deep, nonlinear research—perfect for organizing thoughts like orb.blue’s.
libraryofbabel.info
A conceptual site that explores infinity, meaning, and randomness through Borges’s famous library. Philosophical, algorithmic, disorienting.