TeensySaber now supports small (128x32) OLED displays.
Currently they will show power level and current preset, but can obviously be made to show anything you like.
The displays come in white and blue, and can be bought directly from ebay, or from me in my teensysaber sales
thread:
TeensySaber V2 for sale (I'm running low on TeensySabers right now, but I will order more as soon as I run out.)