I became a PTL member because I am interested in 3D Printing and other geeky things - usually with Arduinos as it's quick and I don't have much time. I don't know what I would print with a 3D printer yet, but I would like to try, and I would like to try with other people who come at these things from different angles.
I like making LEDs blink, and ideally using sensors to make things move or make noise. I have done a few projects since joining PTL, and have plenty more in the pipeline (note to self: must learn to weld).
The first project was a twitter light. An ambient coloured LED that responds to twitter messages. https://www.posttenebraslab.ch/wiki/projects/twitter_light
The next one was a programmable musical instrument built from totally open source hardware https://www.posttenebraslab.ch/wiki/projects/arduino_monome
A next project is my 3D Printer. I chose the Shapercube http://www.shapercube.com as it uses an arduino controller like the reprap, but is made of very solid aluminum walls - looking a bit like a chunky metal makerbot. After about 5 solid days of work, or 1 year of real time (I do seem to be quite busy) it is alive. Test prints start this week.
In an ideal world I would build a very cool MIDI laser harp in the next few months Update: January 2011: I have started on lasterharp#1 you can see progress at https://www.posttenebraslab.ch/wiki/projects/laserharp1 Update April 2012. It looks much the same
Another project is a scrolling LED matrix display, like you see on the TPG buses. https://www.posttenebraslab.ch/wiki/projects/scrollingLEDmatrix