Just say "Hello? Hello.....? You still there?" They get really loud trying to get your attention back.
Just scream at them. They don't count as human beings until they can get a real job, so show no mercy.
Tell them you're interested in a product they aren't selling. If they want to sell you a credit card, act like they're selling you homeowner's insurance.
Ask them what time it is, and after they tell you the time say "Nope, it's TOOLTIME with Tim the Toolman Taylor!"
Ask them what their Newground's alias is because you want to see if they've made any flash.