Some of us in the UK have been developing a new product called Nanode.
Nanode is a very low cost device which will be used to connect up the Internet of Things.
It's compatible with Arduino Shields and the Arduino IDE - but comes with an ethernet controller on board all for the same price as an Arduino Uno. (22GBP 25Euro 40USD).
The first ones are being shipped as development kits, which you can easily build yourself.
So you have an open source internet connected device very cheaply which you can then experiment with internet connected smart sensors and the Internet of Things.
Read more about Nanode here http://hackerspaces.org/wiki/Nanode
And here http://www.nanode.eu/
The next batch of kits will be ready in mid-June
If you are interested in Nanode - follow @Nanode_1 on Twitter or email nanode at hotmail dot co dot uk