Made a few breakthroughs with Arduinos on a G4 with OSX 10.4. The Arduino site has an older IDE which still works on G3 & G4 OSX Macs.
But there is a problem with some Arduinos made in China and sold on various sites like Ebay for under $10 (even lower than $5!). Most of them have their BootLoader missing. This is a simple fix, but it requires a working Arduino like the Arduino Uno R3 with a working Bootloader. See this webpage on how do do it: http://www.instructables.com/id/How-To-Burn-a-Bootloader-to-Clone-Arduino-Nano-30/?ALLSTEPS
But this does not fix the problem totally. Ther