Here's a fun little project that can make big, fat, noisy sparks at least 2 inches long, and can be built very quickly and cheaply.
http://www.electricstuff.co.uk/marxgen.htm
How to measure that HV with some precision.
http://home.earthlink.net/~jimlux/hv/spherev.htm
Covers theory, tips, pratical advice, sources, parts, links to other sites, and information about HV probes uses and design.
http://www.repairfaq.org/sam/hvprobe.htm
Comprehensive tables that relate NST volts to various other parameters of the TC.
http://hot-streamer.com/TeslaCoils/Misc/NSTStudy/NSTStudy.htm
Testing of Flyback (LOPT) Transformers
http://www.repairfaq.org/REPAIR/F_flytest.html
HeNe Laser Power Supply Design
http://www.repairfaq.org/sam/laserhpd.htm
:SAFETY Guidelines for High Voltage and/or Line Powered Equipment. Be careful, the life you save may be your own.
http://www.repairfaq.org/REPAIR/F_safety.html
Scientists discuss the statistics, biology, and safety at the ICAE. What happens when people and lightning converge.
http://spacescience.com/newhome/headlines/essd18jun99_1.htm