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POPSMake your own info-via-SMS service Simple but cool: enter some text you want to publicize, and a keyword. Then, whenever someone SMS's that keyword to 41411, they get a return SMS with whatever information you've published. Like a mobile faxback service.
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POPSMyTago: Put hyperlinks on real stuff in real life! Sort of like semacoding. Print barcode-like labels and stick them to things. Then photograph them with your cameraphone, upload them to the web, and decode them; they function like hyperlinks. MyTago can even OCR text from photos.