I was just revisiting 20q.net, reminded after seeing the ontogame site. The latter starts with a Wikipedia/dbpedia concept, and asks you to classify it according to some ontological criteria, I think drawn from Proton. The former (neural-net based I think) lets uses supply random concepts, and when needed provide distinguishing yes/no characteristics. I wish all such sites pumped their conclusions (or a subset) back into the Web, perhaps under the new open data license (see also semantic-web thread).

Here’s 20Q’s attempt to guess the location I was thinking of (Bristol, where I live): 

Q22.            I am guessing that it is Bristol (England)? Right, Wrong, Close
21.	  	Is it very noisy? Sometimes.
20.	  	I guessed that it was Lancaster (England)? Wrong.
19.	  	Is it popular with teenagers? Sometimes.
18.	  	I guessed that it was Carlisle (England)? Wrong.
17.	  	Is it known for volcanic activity? No.
16.	  	Is its official language English? Yes.
15.	  	Is it associated with a team sport? No.
14.	  	Is it small? No.
13.	  	Is it located in Scotland? No.
12.	  	Is it a city? Yes.
11.	  	Is it hilly? Yes.
10.	  	Does it have wild animals? No.
9.	  	Is it located in Canada? No.
8.	  	Are cars often seen there? Yes.
7.	  	Is it located in the western hemisphere? Yes.
6.	  	Is it made of wood? No.
5.	  	Do people live there ? Yes.
4.	  	Is it found in a warm climate? No.
3.	  	Is it a crowded place? No.
2.	  	Does it have a specific tourist season? No.
1.	  	Is it located in the United States? No.

After I said “yes”, I got this feedback:

It is Bristol.
Is it associated with a team sport? You said No, 20Q was taught by other players that the answer was Yes.
Contradictions Detected
The opinions of the 20Q A.I. are its own, and are based on the input of players. 20Q's answers reflect common knowledge. If you feel that 20Q is in error, the only way to correct it is to play again!
Similar Objects
Carlisle (England), Spokane, WA, Lancaster (England), Providence, RI, Walla Walla, WA, Belfast (Ireland), Launceston (Australia), Bainbridge Island, WA, London (England), Brighton (England), Butte, MT, Durham (England).

Huh, we have a sports team? Who’d have thought it? I guess some things are subjective…