Stuff to look at
Bestiario - data visualisation, artificial life, swivelly website.
Information Aesthetics - form follows data - data visualization & visual communication.
Paul Neave - interactive playground.
Mike's Electric Stuff - dangerous fun!
Useful Software
Processing - FREE - "Processing is an open source programming language and environment for people who want to program images, animation, and interactions. It is used by students, artists, designers, researchers, and hobbyists for learning, prototyping, and production. It is created to teach fundamentals of computer programming within a visual context and to serve as a software sketchbook and professional production tool."
Arduino - FREE (software), CHEAP (hardware) - "Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments."
Zoho - FREE - online office and presentation tools and embeddable widgets.
Widgetbox - FREE - loads of embeddable widgets, plus make your own widgets and panels.
Fraps - CHEAP - very good and easy to use Machinima capture software for OpenGL and DirectX apps. Free demo version to get you started.
CamStudio - FREE - make videos of your desktop as you work. Comes with its own lossless AVI codec, which you should use as the other codecs don't provide great quality.
Yahoo Pipes - FREE - mashup tool - "rewire the web".
PopFly - FREE - mashup and games creation tools. Uses Microsoft Silverlight technology.
Project Draw - FREE - online/offline diagramming tool from Autodesk.
Pachube - FREE - "connect, tag and share real time sensor data from objects, devices, buildings and environments around the world"