Where can I find a database, preferably OWL-based, that contains structured information about everyday objects? I'd like a database that has information like that fact that a table is 


made of wood
is composed of a top and legs
is used for eating food off
etc


And I'd like this information to be semantically structured, rather than in natural language. By that, I mean that I would like there to be an ontology defined with terms like isMadeOf, hasColorOf, isUsedFor etc, so that it becomes easy to select all white objects, or all objects made of wood etc.

Is there such a publicly available database or something along those lines? I've found ontologies such as OWL that, if I understand correctly, define things like ways of noting that two objects are symmetrical etc, but I haven't so far found any decent size databases that contain actual knowledge. 

Many thanks for your help!
Cyc is similar to what you are looking for. It is a database of general knowledge and is organized semantically. It is free to use for research purposes.