pauls point about the ouyer layer of skin is well taken.
I remember taking a course with Joe Tedesco about 15 years ago and we discussed an electrician being electrocuted by the filament of a broken temporary light.
The energized filament punctured the skin on the back of his neck and killed him.
To illustrate this, next time you have a minor cut, simply touch the probes of a DMM with your dry fingers then do the same with one finger and the wound. Compare the readings. You can also try comparing dry finger readings to that with a little bit of saliva on your fingers. Again, a dramatic decrease.
Doing the math will show that you are much more likely to get to the 70-100 mA threshold of defibrillation through an open wound or while damp.
Also remember that surface area plays a big role.
The resistance from finger tip to finger tip is much higher than that from a the palm of your hand wrapped around a pipe, or your forearm tightly pressed against steel work.

Scott's point regarding wattage seems to more so addresses the "cooking" of internal organs, than heart and muscle spasm type electrocution effects.




[This message has been edited by Redsy (edited 04-17-2005).]