This happened a while ago, but it's definitely one of those WTF situations, so I had to share.
A few years back my sister and I had a family plan with Sprint. We had the phones for quite a while beyond our contract, and never had any problems beyond your average dropped calls and poor reception from time to time. Well, I've never exactly been a calm person, so one day when my phone dropped an extremely important call I became very frustrated and decided to get revenge by smashing the phone. Yea, stupid, I know, but I was already a bit emotionally off because of the phone call. A few days later we call sprint to cancel that line, because I decided to get my own plan with another company that wouldn't drop my phone calls. The woman tells us that we can't cancel the plan because we can only do something like that on the first day of the billing cycle. This struck me as weird, but I figured oh well, I'd be charged the $10 for the month anyway, so I can just wait. Next month rolls around, and we get the bill for that cycle. There's $200 worth of calls to Jamaica from my number! What the hell? We call Sprint and tell them that these calls clearly could not be made by me, that I don't know anyone in Jamaica, and that as we told them last time, my phone was broken. I ask them if it's possible that someone had cloned my phone. For those who don't know, cloning is when someone attaches your number, and service, to a separate cell phone. I know for a fact that this happens because I know people who've been in that "business". The Sprint rep tells me that it couldn't have been cloned, there's no such thing as cloning, and I made the phone calls. I tell them that I can send them the broken phone if they don't believe me, and they pretty much accuse me of lying. I ask to speak to a manager, and I'm hung up on. I call back, and finally get a manager, and explain the situation. The manager claims they have a tracking device, and they can trace the call back to my phone. Yea, right. I'm no rocket scientist, but I've worked in electronics, and I know that's pure bullshit. I ask for someone above them, and they say there's nobody there above them at the moment, and I'll have to call back the next day. I search my house for the remnants of my broken phone, just so I have it if I need proof, and just to be sure there's nothing missing that could give someone access to my service, and it's all there. I call back the next day and speak to the same "manager". This is where it gets really weird. The guy offers us twenty dollars to "resolve the matter". I assume he means something along the lines of a twenty dollar credit to our bill, in addition to them clearing the $200 in fraudulent charges. Not quite, he means twenty dollars to just let the matter "go away", and to keep me from speaking to a real manager. I hung up the phone on the guy, and waited to be contacted by someone from billing, because at this point I was convinced that it was some inside scam. I had been lied to by every rep I had spoken to, and just didn't want to deal with it anymore. About two years later we finally get that call from the billing department. We tell them what happened, and they try to tell us that we still need to pay the bill. My mother, who is normally very calm, and believes that law suits and never the way to go, threatens to call a lawyer and tells them that she'll own the company by the time she's done with them. Go mom! They decided my whole family was way too nutty to deal with, and wiped the bill clean.
I still wish I knew what exactly happened, but I guess it would be impossible to find out.