the This is a great little, Arduino compatible board, which has an XBee slot on the back, making it cheaper than purchasing an Arduino and XBee shield and also giving it a much much smaller form factor. It is compatible with the Arduino API although you need to download the Funnel library as it has some other functionality. - well worth a look

funnel.cc | Hardware / FIO

It based on the original design from LilyPad Arduino v1.6. It has connections for a Lithium Polymer battery and includes a charge circuit over USB. An XBee socket is available on the bottom of the board

A Useful tute from
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» DS18B20 Temperature Sensors and Arduino
Spent the day working with DS18B20 temperature sensors and getting an Arduino to read the data they spit out.  Lucky for me and you, we have the shoulders of giants to stand upon as we copy and paste some magical code to get us started

DS18B20 Temperature Sensors + Arduino from Morgellon on Vimeo.