When I was in Japan, I loved the fact that there were QR-Codes all over the place – QR-Codes are two-dimensional bar codes that can be "scanned" (i.e. photographed) with any cell phone with camera. The camera would then decode the QR-Code and visit a URL, call a phone number, etc.

There are QR-Generators online, and the code shown here is for jastram.de. I found this on PDA Geek.