An anonymous reader writes: Spam filters have come a long way over the past two decades — but spammers have, too. Though email providers are better than ever at blocking spam, it's still big business, with a lot of money to be made. Security researchers are seeing a new trend in spam: less volume, and better targeting. The article mentions "snowshoe" attacks, which occupy the middle ground between massive spam campaigns and tiny phishing attacks. "Craig Williams, a senior manager at Talos, said the amount of snowshoe spam has more than doubled in the past two years and now accounts for more than 15 percent of all junk messages distributed globally." Security researchers have been pushing for a unified registry to help deal with these mid-range spammers, but it's hard to get a significant portion of providers on the same page, particularly when many are fond of running their own solutions.