Thank you peerless and Aaron for your input. I'll have to get around trying that nuke thing. This thing has had me so stressed out and sleepless recently. I feel like the only way to make sure things don't turn bad is to go to the authorities and tell them what happened, but I fear they won't believe me. Is there any way to anonymously ask for advice from the authorities on this matter?

I personally stay away from all filesharing, newsgroups, and any other unsafe house of porn. I don't know how many of the cases where people in this thread who got in trouble are actually an accident or they are just lieing to themselves, but I would not take the chance. Through a combination of the justice systems and general publics ignorance of technology and incredibly harsh laws for mere possession, and then with filesharing it becomes 'promotion' as well, it's simply to risky to go to those places for good ol' legal pornography.

This article should rightly scare the pants of you if you downloaded anything like that; these guys are in the worse possible position. It's impossible to tell who might be a victim of circumstance and who has a major problem with this kind of stuff because they lump them all together and call them 'vile, disgusting deviants'. Thanks to recent Florida law changes by politicians looking for easy targets, these guys are facing the same kind of sentences murderers face.

19 Arrested in Child Porn Bust | TheLedger.com

One of the accused-
'Mitchell Parker, 22, of Lakeland said he didn't do it.

"I'll say one thing, don't ever get Bearshare or Limewire," he said, denying that he ever downloaded the illegal material. "I am disgusted. I wish I was in a battery acid pool right now." '

Oh my god. Guys that article has me truly terrified, I fee like just crying. Should I just go to the authorities?

Sorry brother, did not mean to terrify you. That sheriff in the article is especially into that kind of crime, he's kinda creepy actually when you here him talk. If you just downloaded half of something and then deleted it I really don't think you have anything to worry about with most professional law enforcement. Despite what they could possibly get you for if your hard drive was not clean, they would see the incident as a very non-intentional one based on that. And the fact is that if you have not had anyone knock on your door yet, very slim chance that you are ever going to. Real federal law enforcement is going to be looking for regular activity and then move in directly after a download or an exchange of some kind so they know they have current, real evidence; not to waste their time with an old half-event like yours. They want to catch people who are actually doing something wrong. Follow the good advice presented to you here, please stay clear of dangerous activity but please have peace of mind also my friend. You are going to be fine.