LOL Luiz!!!
I don't mean to make light of what you perceive is a threat to your good name... I am laughing because the whole Internet is just such a funny, funny thing!
"Yeh, it has to be from Luiz: look-- see, he's wearing a 48GX!!"
Man, I know what you are going through. In November, while I was eBaying a lot, one of the vendors had me in their "Contacts" list in their Outlook Express. They somehow got infected with a virus. I know this, because one of the things this virus did was take that list of contacts, send an email to each of us which contained the virus, and it proceeded to infect MY computer and send MY Contacts the same...
I stopped that fast, my external modem was going crazy showing uploading, and I pulled the plug. But I might not have noticed anything otherwise, had I just been puzzled by the nonsense mail I got.
I was MAD, really angry. I had to rebuild my Windows system, bought Norton Internet Security, went to using Yahoo mail for a while, and ultimately configured Outlook Express to NOT automatically open everything that loads in or is clicked on. While I trust Norton for most things, if someone sends me something and I don't know them or it has an attachment or I am the least suspicious of it, I don't open IT-- I choose Properties and I examine the SOURCE. Or, mostly, I just delete it (practically impossible to just delete a mailbomb if you use Outlook as it comes initially configured, with that Preview pane ON).
Luiz, I was paranoid for a month-- but virii and unsolicited crap-- AND, I guess you know, your published identity, no matter how many times you change it-- are all going to swirl around this toilet bowl known as the Internet. Even my MOM has received unsolicited porn, and she's not been out there trolling for anything but gardening advice.
The best advice I know of is to keep your profile low, maybe when you put your name out there, you do it with a misdirection, like the "luizNOSPAMvieira@quantica.br" idea. Or, as in my participation here, I invite the feedback ALSO to be here, and don't post an email address. The less its out there, the less exposure to evil, and I know the mail I see in my box is actually from someone I want to hear from.
Finally, I don't OPEN (or allow Outlook to open) anything I am not confident is a legitimate correspondence.
Luiz: do whatever you feel makes you more secure... except leave the scene.
In my hometown, all my grade-school teachers were in the phonebook, and you knew where they lived. This meant, sometimes, that a little jerk like me could call and ask at 10pm: "Is your refrigerator running?" (an old joke that 11-year-olds always seem to think is funny). "Ooh, you'd better go catch it then". Unlike now, there was no "caller I.D." function. I'm sorry now, teachers. :-/
On today's Internet, Luiz, telling what came from whom is almost impossible if someone wants to decieve or be unknown. The "Caller I.D." function in email is pathetic, to say the least. Even on this board, someone can type your name or mine to their post.
But our reputations are never going to be made nor broken by others' misuse of our identities: those who know us, or need to know us, will not be misled when or if such a prank occurs.
You are not a prankster, and we all know that. While I *sometimes* am capable of pranks and foolishness, I stopped cold using any alternate pseudonyms here out of respect for Dave's Rules, when they came about. Darnit, no more "Mr. Guaca Mole", no more "Joy S. Noel", now it's only "glynn", always "glynn". And when I want to say something "arrogant" or silly, I take the flack.
No one here will ever respect you any less, if your character HERE is consistently as praiseworthy and helpful as it has always been. Notice that you, here, are QUITE respected, and have been from the moment this crowd started reading your posts. That will always continue.
Gosh, even if you're NOT a swinger... ;-D