Zone of ai-claimed and settled worlds some 10-20 ly from Sol.
After being expelled from the Solar System in the Interplanetary Age, many ahuman and solipsistAI entities colonised nearby systems and built themselves virtopias. Most of these systems were red dwarf stars, but the brighter stars Altair and Procyon were also claimed. The Diamond Belt got its name from the observed fact that most of these entities used diamond-based computronium for data processing.
In many cases they were total isolationists, hogging resources but not doing anything. The Diamond Belt AIs formed an interesting political group in the Inner Sphere; sometimes actively hostile, sometimes simply non-communicative, occasionally bizarre. For the most part these systems were considered no-go areas for human colonisation efforts.
The Diamond Belters generally operated independently of each other, and many sent out waves of secondary colonisation which became the Diamond Network and the Solipsist Panvirtuality. Today most former Diamond Belt systems have joined one or another of these two metaempires; some, on the other hand, have become integrated with the human-friendly Sephirotics.
Charybdis - Text by Anders Sandberg LTT 17897 III; a carbonaceous planetoid orbiting the dim M4 star LTT 17897. Notable for the signs of massive nanofacturing on the surface, tentatively dated as the 27th century. It is believed that it was used to launch von Neumann probes outwards, but no sign of the builders have ever been found and no aioid clade claiming descent from Charybdis has ever been found. The nanodefenses appear similar to the nanodefenses found on Duoden Torus.
Duoden Torus - Text by Anders Sandberg Wrecked structure orbiting Hip 74815 at 5 AU. The structure is a torus of diamondoid meshwork 3 kilometers across, with a small radius of 43 meters. On the meshwork are computing nodes similar to 5th century terrestrial quantum cellular automata. It appears to have been partially destroyed by an antimatter explosion nearby, and all information states lost. The defenses appear similar to the Charybdis installation, suggesting a common origin.