Touchless

Touchless is an open-source application framework that enables you to use your webcam as a multi-touch interface.

via lifehacker:

"Right now the Touchless Demo lets you play with four proof-of-concept ideas: Draw, Image, Snake, and Defend. The first is a free-form drawing application, while Image is an image manipulation utility that allows you to zoom in or out and move around on a map with marker gestures. The other two are games (Snake is exactly like the classic, and Defend is up to four-person Pong). To set up a marker that Touchless tracks, just grab something colorful, click Add A New Marker, then draw a circle around the object. From there on out, Touchless will monitor that marker wherever it is in the shot. Right now the application is a little clunky, but as a proof-of-concept it's not bad (and it's fun to play with)."

atomswarm

atomswarm is

"a framework for performance and composition, based on swarming behaviours similar to those seen in flocks of social animals. It can be thought of as a self-organising ecosystem, whose structure is internally regulated by limited resource availability and each agent's pursuit of internal homeostasis.

Sonic behaviours are determined by each agent's genetic disposition, the relationships between agents, and the population's continued evolution over time."

I saw a performance/demo of this software at a conference and was impressed. Whilst it can sometimes be hard to associate the onscreen movements with the generated sound, the majority of the time things do make sense. The output of the system looks and sounds very impressive.
At the website you can find links to video and audio as well as a description of the project along with examples of the code used.
The site also contains info on the developers other projects

Sending & Receiving SMS within Processing

via digital tools I found this site by Bryan Chung who has ported a java library for communicating with SMS messages into code suitabel for use with Processing.

I have been gently looking for something like this for a while as it could come in handy for use in installations - origianlly I was trying to get it to work straight in MaxMSP, but this could be an alternative - it's possible to pass data between Ma xand Processing.

Arduino Tutorials

The Arduino is a physical computing platform which you can interface with your computer. It is possible to 'code' the Arduino board to implement various functions and to be controlled by various software packages such as MaxMSP and Processing.

Here are some tutorials for info on how to code your board for certain projects:
this site has numerous step by step tutorials on the Arduino board plus a few tutorials on soldering and other related, useful topics.
this site contains numerous tutorials for projects such as controlling LEDS, controlling motors, using sensors, etc..

You could also visit Make and Instructables for other tutorials and projects.