McDonald's uses mobile phone readable QR codes for "nutrition" information

QR Codes are a matrix code (or two-dimensional bar code) used to store information which is more effiect than the traditional bar codes that we are used to. McDonald's Japan is now printing QR codes on all its food packaging so you'll know exactly what you're eating (if you want to know, that is). To read the info, you simply scan the QR code with your cellphone camera, which should automagically recognize it and direct you to a mobile website with the lowdown on the contents of your McFood, including any potential allergy warnings. For the two people in Japan that don't have a camera-equipped cellphone, McDonald's is also printing conveniently short URLs for the corresponding mobile website. Of course, all this info only is really more of a curiosity, since you've likely already bought the food by the time you're snapping pics of it with your cameraphone.
You can generate a QR code for your website, phone number, text or sms message Kaywa QR-Code Generator.

Kaywa Reader For Mobiles

QR Codes originated in Japan to tag auto parts, but have expanded to become a way for mobile users with cameraphones to quickly link to online content from print ads, products, magazines, you name it (including booth girls at tech conferences, and Matt Joneses eternal struggle to get a 2D code into icons and all else). Fully half of all i-mode users in Japan have used QR codes, according to RFID in Japan.

So, Kaywa has created a QR code reader that fits nicely in your mobile, and also a code generator so you can create your own code. You can also test it on a few sample codes on their site as well, and download some music if you are so cool as to be in Switzerland, where they are based.
Visit qrcode.kaywa.com to generate a QR code for your URL, text, phone number or text message. The QR code on the side was generated there for this blog.