Thanks for the notes about your setup. I wasn't familiar with JTAGICE, but for $99 it looks like a great programmer and debugger. I assume the only advantage of the Dragon over JTAGICE is the high voltage option for disabling reset fuse? I'm guessing I can use it with avrdude under Mac, and then if I want to get the debugging capability I can run AtmelStudio under Fusion (which I have but was hoping to avoid starting up Windows XP). This is all just hobby stuff for me, so I'll also look at the Arduino option too. I had read a tutorial about using an Arduino as a programmer (and even a high voltage fuse resetter), but I thought the ArduinoISP sketch was geared only toward loading Arduino sketches onto ATtinys. (That is, I want to program ATtinys without the overhead of the Arduino timers and other libraries.)
Thanks again and please let me know if anyone figures out why USB3 or newer machines don't play as nicely with the USBtinyISP. I'd be happy to assemble a new programmer if there is a revised chip or firmware that solves this. And I'm also adding a JTAGICE to my Christmas list.