K, here to start with, lets get the trojans out of the way. Sub7 and all those trojans are files people have been binded to some programs. Binders are special programs that bind a trojan to a legit file to make it harder to find. Now the reason you may find more trojans in mail bombers is because mail bombers are not very mainstream files, people normal people sit around and code them, so people get access to them easier, they don't have to pay for it. You will in general find more trojans in fiesl associated with hacking. Also I think the reason they do not work for you is because you need a valid e-mail server that is willing to send your e-mail without a login. Most mail bombers come with a list of e-mail servers, but those rarely work, so you are left trying to find one on your own. Hope this helps.