If your smartphone has a built-in camera, have you tried NeoReader or Microsoft Tag Reader? It's a great little app that allows you to scan a square matrix code (also known as a QR-code, Quick Resonse code, a 2-D bar code, and more). After you scan this code, your phone will open a web browser so that you can have access to additional information.
These types of QR readers will become ubiquitous in the near future. You won't be limited to Android smartphones. NeoReader is currently available for smartphones running BlackBerry, Windows Mobile, and also for many non-smartphones. Microsoft Tag Reader is also currently available for many different types of smartphones and standard phones that have built-in cameras.
Have you tried using these mobile QR code readers? What's been your experience?