founder craig newmark about the site's safeguards. it created quite a sensation. take a look. >> i want to show you how easy it is for these pimps to use these ads. we'll post an ad for a fictional prostitute right now. don't try this at home. it says it will cost $10 per ad. $5 to repost. one of the big things going on with craigslist, they're saying they're monitoring all these ads that come through an adult services to check to see if any of these girls are underage or young. so we put some words in here, sweet, innocent, new girl. we'll see what happens. we'll see if craigslist will let our ad post. we'll see what kind of calls we get. >> i saw your ad on craigslist. >> hello? >> yes. what's your donation -- >> what are you looking for? what type? >> oh, just half an hour. just a quick half an hour get together.