Fuck YAHOO!
Back in the late 90's they decided to get into selling porn and attempted to split theirs users into two groups….adults and child. Caused no end of trouble for a local hobby club I was part of when we were using their "yahoogroups" mailing lists after they bought out eGroups. trouble is they forgot (yeah right) to change their algorithms and they started serving up porn images to children. They decided to get out of the pron business not long after. Luckily as a moderator for the clubs mailing lists I was able to shut things down with only one 16 year old being exposed to the ads. We went to our own server based system after that.