Adafruit Gemma and Trinket Blink Sketch
Note Pin #1, instead of Pin #13 is the on-baord LED for both the Gemma and Trinket boards.
This is a useful sketch to verify you have your enviroment set up correctly to program Gemma or Trinket via USB. I use Codebender since after struggling to reliably program either the Gemma or Trinket using Ubuntu.