Interactive document collections equipped with affective computing, making them develop a bond with the owner.
Originally developed as a marketing trick to save the flagging ebook market during the late Information Era by EBK Solutions, but later regularly revived in new forms. These include the fad in organic petbooks of the First Federation and the fake stray petbooks (intended to seek out and be saved by compassionate people) spread by Sophic missionaries in the 8900's. Petbooks are somewhat related to advanced madverts, and various hybrids exist. The most well known and feared is the feral libraries of the northern plains of Nova, where large swarms of petbooks infected with madverts search for food and customers.
Pet Rock - Text by Todd Drashner with note by Anders Sandberg Slang term for a world, terrestrial or otherwise that has had its surface structure modified by a transapient or archai, apparently for the esthetic enjoyment of the creating entity. Apparently created for reasons similar to why some terragens practice pottery or sculpture. Occasionally found in systems that host archailect primary computing nodes and tools. Some pet rocks result from interacting MPA and Keter cultures, holding exhibitions of von Neumann art in otherwise unnused systems.