If you have communicated in any way with anyone who posts this SPAM, please DO NOT SEND EMAIL to me or to anyone else until you have verified that you have NOT BEEN INFECTED.
At best, you have confirmed to the SPAMMERS that they're little game is working. At worst, you have sent them your email address so that they can now "phish" you, or otherwise attack your computer to infect it, so that you can be a participant in spreading their crud.
It would be recommended practice at many companies to reformat your hard drive and reload everything if you are known to have "clicked" anything from any such message.
NEC, Samsung, and Hitachi are all reputable companies who DO NET SEND SPAM and DO NOT POST ADS except by legitimate invitation. They, along with mudcat, are possibly VICTIMS of whoever is running the attacks on mudcat.
The "ads" to which you responded probably are just links picked from someones browser favorites, on a machine controlled by whoever is making the attacks on mudcat, but they may have been redirected to the originator/controller of the attacks to find additional gullible and defenseless "prospects" for infection.
Since you are now known to have replied, you are now on my list of those guilty of childish, immature, and ignorant email behavior, and until a sufficient time has passed to demonstrate that you have not been infected, and until evidence has appeared that you've learned better web manners, I would not give you my email address under any circumstances. As a favor to others, I would suggest that you DELETE the email addresses of all your friends from your email address book until you verify that you are not at risk. (You can back up your address book so that you can restore addresses later, but I certainly wouldn't want my address where malware on your computer can access it.)
I would suggest to anyone who has your email address in their own address book, that they remove it at least temporarily to permit their ISPs filters to block compromised messages from you. That's a choice your friends will have to make.
BAD IDEA. (On a par with offering to give etiquette lessons to a biker gang.) Good luck.