When publishers sell advertising on a CPM (cost-per-thousand impressions) basis rather than on a flat-fee basis, the value of content depends solely on the amount of traffic it can draw to websites and newsletters where ads are displayed. This dynamic has reduced too much web content to the equivalent of internet-forum trolling -- provocative pieces designed to "go viral" by sparking controversy and outrage. Publishing top 10 lists that few people agree with, politically charged short video clips and other pieces of "link bait" that aim to get people to express a contrary opinion has become a viable online publishing business model. Just ask Cracked.com.