I was calling DirecTV to cancel my service (long story that involves a major douchebag). After waiting a few minutes, I get on the phone with a guy. They need to speak with my dad because his name is on the account (we bundled it with his phone service, yada yada). Well, he isn't in the state. BUT, iPhones have the conference call feature. I tell the dude to hold, call my dad's cell phone, merge the calls, and BOO YAH. Score another point for an iPhone feature. It couldn't have been much simpler for something I had only tried once before.