The hardware included in the "Projects" section is built mostly using Arduino (www.arduino.cc). We favor Arduino for a set of reasons. Although not the most powerful platform it is very easy to interface with other hardware. It is built around MCUs that can work with very low power consumption. It has a rich set of libraries for a variety of purposes. It has a dedicated IDE. This way the learning curve is very easy.
Or if you want to be completely in the cloud you can use Codebender's Arduino online IDE (www.codebender.cc):
We also favor Raspberry Pi. We prefer this whenever the software needs are high and the Arduino platform cannot handle them. The disadvantages are the lack of certain inputs/outputs on the GPIO (this could be changed since we published this page) and the fairly low load supported on the outputs. Usually a combination of Raspberry Pi with Arduino could give you the best results.
A very good alternative to Arduino is mbed (www.mbed.org). Built around ARM processors this offers a more powerful platform than Arduino with some of the advantages you get working with Arduino (standardized IDE, easy to learn, etc.). It also has an online development environment.
In general we recommend open platforms because they are very cost effective to start your own projects. Once you move into more complex projects or have special needs we encourage you to use your preferred platform.