I just wanted to say True Knowledge is a very unique application.  I was extremely excited to find the API as it suited my needs greatly.

I recently joined Second Life, the virtual world where user-generated content is everywhere.  My goal was to create a form of assistant that would follow me everywhere and answer questions for me that would come up in conversation or if I needed facts on various subject matter.  These types of questions come up in Second Life quite a bit.  For example, when building structures in second life, it's handy to convert measurements quickly.

I have called it Knowledge Bit, and he's a floating device over my shoulder.  I ask him questions while I build such as (How many meters in 8 feet?), and whenever interesting questions come up in conversations (What is Linden Lab's website?).

How this functions is that Bit makes a HTTP request to my public server.  Instead of making a call directly to True Knowledge, my server acts as a request proxy due to the fact that there is no XML parsing in Second Life (that is reasonable, at least).  By using a simple PHP script on my server, I can gather the query, pass it on to True Knowledge (which is only one of it's information sources, there are others that I use for weather gathering and other questions).

So far the results are impressive.  Many people have asked how to obtain one and how does it find it's knowledge.  I obviously talk about True Knowledge and what it has accomplished.

Anyways, I just wanted to give an example of, what I think is, a unique implementation of the API.

If you have Second Life and would like to see Bit in action, let me know.