amoral dilemma (hacking/cracking ethics)

Yes, the spelling was intentional.

I just noticed that there seemed to be a lot of activity on my cable modem when I wasn’t doing anything particularly net-intensive. So after poking around a bit, I discovered someone was browsing the shared folders on my system.
After a bit more poking around, I found his ip, and started browsing his shared folders.
Now, the problem I have is that this guy seems to have his entire c: drive shared. There could well be information on his system that he does not want to be world readable. After skimming the file system, I’m nearly positive there’s info he doesn’t want the world reading.

I have his full name and access provider, so I could presumably find an email address. I also have access to his printer, so if he has it turned on, I could print something out. But I fear that if I warn him of his vulnerable system he will take that as a threat or evidence that I have already compromised his system. He could well already know I’ve been there (he didn’t seem to be completely clueless from what I saw).

How should I handle this? I can just leave it alone and let him stay open for anyone to go in and read anything they want from his computer. Or I can risk being a blamed messenger.

What do you think?

My philosophy is ‘punish the stupid’. Don’t tell him. When someone seriously fucks up his system, he’ll learn.

He started it by rummaging around your system. Delete something.

I don’t believe I have write access to his system, just read access. So do you, if I were to tell you his IP.

I didn’t check for write access, but if he did leave that open, then yeah, he probably does deserve for someone to drop 3 gigs of latvian midget porn onto his desktop.
But I’m not gonna be the one to do it.