Has anyone taken a look at the OpenCyc project?  Here's an overview I
snipped from their website:

OpenCyc? is the open source version of the Cyc? technology, the
world's largest and most complete general knowledge base and
commonsense reasoning engine. Cycorp, the builders of Cyc, have set up
an independent organization OpenCyc.org, to disseminate and administer
OpenCyc, and have committed to a pipeline through which all current
and future Cyc technology will flow into ResearchCyc? (available for
R&D in academia and industry) and then OpenCyc.


This project seems to hold a great deal of promise, imho, as teaching
a computer "common sense" seems to be the first step in a number of
applications.  The project is still in it's infancy but they have
released a first version of the database/application.  Unfortunately
the interface is entirely JAVA-based at the moment although there are
plans to support other languages.

From reading their messageboards it seems more people are confused
than inspired by this project so i'm hoping an influx of ruby
programmers might get the ball rolling for some type of ruby-based
interface!

This is the documentation webpage: http://www.opencyc.org/doc

This is the OpenCyc messageboard:
http://sourceforge.net/forum/forum.php?forum_id=85727