Along the same lines as your email scraping idea you could have users create accounts at your site and give them some string to put into their news.yc profile t

Along the same lines as your email scraping idea you could have users create accounts at your site and give them some string to put into their news.yc profile to prove they own that news.yc account. To make it worth their wild the string could be, say, a link that resolves to a map of their location on hackrtrackr.