Ajax Examples that work

Some working ajax examples:

ajax-get-body.html

ajax-get-xml.html

ajax-get.html

ajax-post-text.html

Testing for Firefox

The following blog entry should test to see if you are running firefox and diplay the appropriate message. I found the code snipit at Dynamic Forums

Building a 3D printer

Check out www.instructables.com for 3D printer projects
Some projects exist that use adruino micro-controllers
The main coding challanges are stepper motor controller, heater controller, convert G-code to stepper motor instructions
Look up mini reprap (repeating replicating)