This article on software piracy, while it will probably not change anybody's mind, at least puts a more personal face on the issue.
Basically a shareware author, curious about piracy, put out a hacked version of his software and uploaded it to a warez board. That hacked version pinged home so he could see the number of people that ran it. It was more people than ever bought his software.
Of course some things he really doesn't mention like just because someone downloaded it and ran it does not mean they are/would actually use it. Maybe they downloaded 4 other similar products as well and are comparision shopping. Maybe like many pirates they are just horders and collect everything, run it once hoping to find something interesting and then never run it again.
I am still surprised by the number of idiots that think that it's okay to steal software because nothing physical is stolen. I've gone over this before but that would be no different than not paying your doctor or your accountant or your gardener or your babysitter or anybody else that only gives you service instead of a phyisical product. What you are paying for with software is a percentage of the the time and effort that went into making it. Your option is to choose to pay what the author asks or not pay and not use the software. Your option is not to say "it costs too much therefore i'm not paying". Try that argument with your doctor.