http://www.spi.org/

The Software Patent Institute and its Database of Software Technologies is a nonprofit corporation formed to provide courses and prior art about software technology to help improve the patent process. The SPI Database of Software Technologies consists of descriptions of software technologies. Each record is all or a portion of a source document that is generally not readily available on-line.

In particular, they do not include patents and most current trade publications; they are interested in the "folklore" of the computing industry. Their source documents include computer manuals, older textbooks and older journal articles, conference proceedings, computer science theses, and other such materials.