Who knows the minds of spammers? I've noticed a trend lately: about 75% of my spam (~30 emails a day) are "apparently from" either "National Refinance Exchange" or "Western Advisory". The actual "From" field generally looks fake (abc123@yahoo.com, and so on).
Blocking those two strings at my ISP has cut the amount of email I have to download by 2/3 (I don't get much real email <sniff>).
I don't get it. Why go to the effort of faking the from address, then sticking an identifiable string in front of it?