I am not sure what the best course of action is for questions like the one on the street sign recognition.
I can't help think the author didn't really search for information prior to answering, and it looks like homework to me. Personally, I am inclined to tell an engineering student to go work on the problem himself, and have some fun.
On other hand, if this site is to become a fantastic knowledge base, I should definitely had my street-sign recognition algorithm and see how the community receives it.