Three Laws of Robotics card-readers in "The Caves of Steel" have a capacity of only a few kilobytes per square centimeter of storage medium. "Aurora", in particular, presents a sequence of historical developments which explains the lack of nanotechnology — a partial retcon, in a sense, of Asimov's timeline. There are three Fourth Laws written by authors other than Asimov. The 1974 Lyuben Dilov novel, "Icarus's Way" (a.k.a., "The Trip of Icarus") introduced a Fourth Law of robotics: Dilov gives reasons for the fourth safeguard in this way: "The last Law has put an end to the expensive aberrations of designers to give psychorobots
Sci-Fi on the Rock readings, auctions and more. In September 2009, Sci-Fi on the Rock put together "Sci-Fi on the Rock TV", a webshow that would appear on YouTube and Facebook, as well as on the Sci-Fi on the Rock website. Each "webisode" runs approximately 10 minutes in length, and would serve as publicity for the festival, as well as a video newsletter, as it were. It is hosted by Steve Lake and Ellen Curtis, and is directed and produced by Darren Hann. The first episode "aired" on YouTube and Facebook on Friday, September 11, 2009. The guests were Darren Hann (Sci-Fi on the