It's every digital denizen's worst nightmare.
You open up your cell phone bill and nearly pass out at the total.
So imagine how a caller named Alberto felt when he learned that his wireless carrier had hit him with a $62,000 bill for downloading the movie "Wall-E" for his nephew.
Last week, he told HLN money expert Clark Howard on CNN that he used a new wireless card to download the movie to his laptop while in Mexico.
"I downloaded the movie and they billed me for $62,000.00," he said. After contesting the charge, the carrier reduced the fee -- to a still painful $17,000.
Even though Alberto's story is an extreme, when it comes to cellular screw-ups, he's not alone.
Paul Eng, Web editor for the Consumers Union, said that in egregious cases, companies will often work with the customer to find a reasonable solution, but it's still best to avoid the situation altogether. And, even though most of us don't fall in the same category as Alberto, we can still fall victim to the same traps.
"Common sense rules here," Eng said. "Make sure you know what's included in the contract. Make sure there are no hidden fees. … You have to be really careful."
He recommends checking your bill every month and contesting a problematic charge as soon possible. If you're about to go on vacation and still want to stay connected, he said it's wise to do some research first so that you know what kind of roaming charges will apply and when.
Most of all, he said, if you're not sure how much a certain activity will cost, it's better to just say no to yourself.
"Resist temptation," he said. "If you just have no clue, better safe than sorry."
Still, even thinking they're doing the right thing, some cellular customers have gotten themselves into a bit of hot water with their phones and wireless cards. Meet five of them.
A Chicago Bear's fan to the core, Wayne Burdick of Schaumburg, Ill., had to cheer on his team -- even while on a Caribbean cruise.
So using his laptop, a wireless card and Slingbox device that let him watch the game via an Internet connection, he tuned into watch the Bears battle the Detroit Lions.
But after a nice relaxing vacation, he returned home to a $27,000 bill from AT&T.
"When I originally got the bill… I was counting on the fact that it was fraud," he said.
But, charging him by the kilobyte, at the international rate, the company said he was roaming for the three hours it took to watch the game.
Burdick dug up the documentation to prove that he was not at sea but actually in port at Miami when he was watching the game, but the company stood firm. Even after Burdick pled his case to 14 different employees, they would only reduce the bill to $6,000.
Finally, after the Chicago Sun-Times ran his story and brought his case up with AT&T, the company dropped the charges.
And, Burdick said, the fiasco was worth at least something -- the Bears won the game.
Gregg Christoffersen called it a "heart attack in an envelope."