2013 was another great year for the Raspberry Pi, and 2014 is already off to an excellent start. The Raspberry Pi foundation just celebrated the second anniversary of the Raspberry Pi Model B board with the announcement that over 2.5 million Raspberry Pis "…have found homes with hobbyists, children and professional engineers around the world."

To me, two years seems even more significant than 2.5 million units. Two circles around the sun, and the Raspberry Pi is still going strong. (The foundation announced two million units back in November of 2013, so half a million Pis just sold in a little over three months.) Two years is definitely too long to call it a fad.

Whatever is causing all these people to buy the Raspberry Pi is something real. The list of customers in the Raspberry Pi Foundation announcement gives a clue to why the Pi has been so successful: "…hobbyists, children, and professional engineers around the world." Seriously, how many products out there are popular with hobbyists and children and professional engineers?

In many cases, an editor can actually get into trouble with the people in suits for trying to target one magazine simultaneously to hobbyists, children, and professionals. They'll say, "Who's your audience? Can't you focus, man?" That's what I love about this magazine – we get to break all the rules because Raspberry Pi breaks all the rules.

This issue rolls out a whole round of inspiring Pi projects for the hobbyist, child, and engineer in all of us. Want to know how to power your Raspberry Pi on a desert island? Our lead story describes some techniques for sizing a wind turbine. We also explore RISC OS, an operating system designed for ARM processors that is gaining new attention with the rise of the Raspberry Pi. We show you how to set up your Pi as a backup device for Apple Time Machine clients, and we look at some tricks for using Rasp Pi on a wireless network. Other articles describe how to set up a homegrown spy cam, use your Pi for instant messaging, and install a web-ready LAMP stack. We also keep up our tradition of including a cool Arduino project (in this case, a temperature sensor with Arduino's new Yún board), and we cover some basic skills for Pi newbies, including Linux file management and more Scratch programming.

Engineer, child, or a child at heart, we salute you! Welcome to the latest issue of Raspberry Pi Geek.