Arduino

Arduino is an open-source electronics prototyping platform made up of open source hardware and software. It’s intended for artists, designers, hobbyists and anyone interested in creating interactive objects or environments. For an example of the type of internet-connected object you can build with Arduino, check out this presentation where the author configured a child’s toy ray gun to react when anyone posted the #barcampliverpool hash tag on Twitter.

Reference: http://www.readwriteweb.com/archives/top_10_internet_of_things_products_of_2009.php