Franz, seeking funding, wants to become the foundation for a “semantic web” : http://venturebeat.com/2008/01/23/franz-seeking-funding-wants-to-become-the-foundation-for-a-semantic-web/

Background:
Triple stores are a way of storing relationships between "things" that is very different from a typical relational database with tables and the like. Rather than mapping things with 1:1, 1:many, or many:many relationships, the relationships are more descriptive, and can take some interesting forms. For example, I know of George Clooney, but we cannot infer that he knows of me. Because of how the relationship is described, we can know that although there may be a connection between myself and George Clooney, it is sadly one-sided. A query to where many similar relationships are stored would likely uncover that I am not alone. Much discussion continues to take place around the storage and definition of these relationships such that they can be used at scale for a variety of diverse applications.

Excerpt:
"Aside from being mind-bogglingly complex, easily involving hundreds of millions (for Wikipedia) to trillions (for the whole internet) of connections, running the program without overburdening the memory and processing power of the computer it’s on has its own challenges.

That’s where Franz comes in, with a piece of software called AllegroGraph. While large companies like Metaweb and Radar Networks (the creator of Twine, covered here) have built their own triple stores, Franz offers pre-built software for companies that want a cheaper and easier way to have their own powerful triple store."