Startup Idea : Tourist Glasses

Imagine going on holidays or to a gallery and popping on a pairs glasses, not your everyday glasses though. How about a pair of glasses that tell you what you are looking at? I imagine that it would work like googles picture search option, you would simply look at an object, building or work of art and glasses would give you detailed information about what you are looking at in the form of a head up display projected onto your glasses.