In a week when we've learned that the Australian government is spending taxpayers' money on pseudo-science, based on little more than half a dozen feelpinions and talkback radio, it's worth remembering that some of the planet's best and brightest are focused not on a mission to Mars or a cure for cancer, but on targeting advertising at you. If you thought those ads that follow you around the web were creepy, well, you ain't seen nothing yet. Advertising platforms -- sorry, social networking and media platforms -- like Facebook and Twitter aren't just collecting the data you give them. They're also buying it in from data brokers such as Acxiom and Datalogix, which in turn have gathered it from banks and credit card companies, loyalty schemes, competition entry forms, surveys that are "just for research purposes" -- anywhere they can legally get hold of it.