A while ago I came across the Where To Get It app that helps us identify + find stuff others are wearing. It's basically a searchable database of street fashion. Then, a few days ago, Amber posted the LeafSnap app that identifies trees by their leaves. Take a photo of any leaf, and the mystery of its name and origin is solved. I did a bit of search and found out that there's also a thing called IntoNow that identifies TV content that you are currently watching, right down to the episode (I guess TV Guide does the same thing, but this seems faster). And then, there's imaginatively named IdThis which strives to identify anything, as long as you submit a photo of it.
A possible useful ID tools that I'd like to see: take a photo of your skin and get a recommendation on the SPF you need to wear. Or a skin care you need to get. And no, this is not based on the lame "diagnostic tests" that cosmetics companies offer, but on an actual searchable database of people's real skin types and their characteristics. Or take a photo of a stain and it's immediately matched with a database of all possible stains to offer an answer.
Shazam was of course the first in this territory of transparent information, and when you think about it, it makes a complete sense to warp a number of processes (search, asking others, inquiring with the experts, looking up our own old stuff) into a single scan. Of course, it usurps the question of expertise (in the cases above: fashion, arborism, music, entertainment), but that's another story.
It just crossed my mind that someone will come up for a "Shazam for people" where you can just snap any random person on the street and learn ALL about them. Hey, just a thought.