Piezoelectric Braille system with PC parallel port control and HV transistors

Here's a project that makes use of these electronic Braille characters: http://www.metec-ag.de/braille%20cell%20p16.html

I built a bunch of transistor amplifiers and use two 74hc373 chips driven by the parallel port to control the state of both Braille characters.

Excellent resource for PC parallel port control:
http://www.beyondlogic.org/spp/parallel.htm