Creating X-rays with a standard vacuum tube

I forced an RCA 811A tube to produce some X-rays by operating the tube in cold-cathode mode at about 20KV and 150uA.  The glass fluoresces nicely, but I didn't get any light from my X-ray intensifier cassette.

MightyOhm's geiger counter kit: http://mightyohm.com/blog/products/geiger-counter/

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