The QR code: gimmick, Pandora's box or just misunderstood?

QR codes. Yuck.

These so-called quick response codes are more like ugly, mysterious trapdoors; more often than not slapped onto designs to convince client that their advert/article/yoghurt is somehow cutting edge. They are designed to be read by machines, not eyes, but are sold to us as superior alternative to simple human-readable URLs. The emperor's new barcode, if you will.

I concede that they probably do have some uses (lord only knows what) and that we shouldn't blame the tools for their misuse. I also admit (and this is rare), that I might be completely wrong. So, this morning I threw a simple straw poll out onto twitter – QR codes: useful or useless? – and was surprised at the volume of responses. Here are just a few:

@gradiate: Pandora's Box … all academic until readers come in built to devices.
@AndrewLey: I love the idea, but personally I can never be bothered to take my phone out, open the application and take the picture.
@jamieparkins: When they are on top of a taxi (as I saw one the other day) or on the underground, useless.
@dte: Useless. They really annoy me these days. It's like people think 'Oh hey, that white space is the right size for a QR code!'
@almonk: Not useless but almost always inappropriately used.
@graphicdrip: More of a problem than a solution in my books. Useless.
@luketonge: Somewhere in the middle … novelty?
@thinkleft: They kinda remind me of those cd-rom business cards from way back. Probably handy for someone, but I don't find them very useful.
@MickStatham_: 100% useless and 200% ugly (if that's possible)
@acejet170: Usefuless … they're the thing of robots. Highly impersonal marks.

As well as this lot, there were a lot that simply said "useless", but none that completely defended them. As well as these, there's Paul Randall blog post about them being no more impactful than scratch and sniff and this article about QR codes out there that allow the user to blindly wander into a mess of malware (thanks to @cottonduck for that one).

So, what do you think? Are QR codes good, bad, or just plain ugly? Have you seen – or designed – something where they're used effectively?