The thing above is a QR (Quick Response) code. QR codes can contain various information including text, links, phone numbers, and even some images. They are primarily aimed at cell phone users recently and are becoming increasingly common in advertising. At the recent Wireless Ready conference, one presentation discussed the way in which QR codes can be used in classes. You see, these codes are easily generated with one of the many online generating services (just google QR cod generator). And once you have the code squares, you can print them out or paste them into a blog or website. You can use the codes to have learners put short texts (up to about 140 characters) into their cell phones. These messages can be saved and learners can take them with them. The presenter at Wireless Ready was doing interactive treasure hunts with groups of his learners. Of course, you could also give some important vocabulary or usage information. The best part is it involves no downloading for either the creator or the user, and no internet access fees.