The Codex Sinaiticus, one of the oldest three bibles known to exist, is now available on-line. The interesting thing about Sinaiticus, and its other contemporaries Vaticanus and the somewhat later Alexandrinus is how unique they are. At this period Christian writings, and the Old Testament documents they were usually based on, were distributed in collections of books, many examples of which survive today. These three are the only "whole" bibles known to have existed for seven or eight centuries.