I was programming my TinyShield and it was working pretty well.  Sometimes the output to the serial monitor was garbled, not sure why.  I clicked the upload button to upload a new sketch, and that action made my iMac reboot. After that, in the Arduino IDE, there was no USB port for the TinyShield.  I think my USB shield just died

I have a project where I want to use the TinyDuino and accelerometer in a low power mode.  Ideally the TinyDuino would sleep for bit, maybe 15 seconds, wake up, check the accelerometer.  I plan to attach the TinyDuino to a the side of a spool that is slowly turning (it's the filament spool for my 3D printer).  If the spool stops rotating, TinyDuino will send out a wireless signal using an RF Link like this one: https://www.sparkfun.com/products/10534.

So I need to know how to setup the TinyDuino for low power mode; I also need to setup the accelerometer for low power.  How do I do this?