I started learning how to use prototyping boards, like the Arduino, so I could build robots. You may want to build other projects like a weather station using the temperature, humidity and rain sensors, or maybe a security system using the motion sensor that is described in Chapter 8, Motion Sensor.
Whatever you are interested in, I challenge you to make some super cool projects with the Arduino. Once you have finished, I would love to see pictures with descriptions of your project and will even post some of them on my blog giving the submitter credit for their project. If you have a video on YouTube of your project, I would love to see that as well. You can send your pictures, and descriptions to: firstname.lastname@example.org.