SubmarineSpam is not quite WikiAsCommercialPromotionTool, but that was the closest page I could find at the time. See SubmarinePatent for the inspiration for the name. I keep meaning to come back and flesh out this page, but I haven't had the time.
The basic idea is that submarine spam is sneaky spam - it looks like an innocent link that would be useful, but when you click on it, you get porno or something. It doesn't exist to get visitors from wiki - it's just there to boost the site's pagerank. An obvious spam link would be cleaned quickly, but submarine spam is designed to slip by undetected.