When the Gibsons of Weyburn, Saskatchewan, in Canada, returned home from a family vacation in Arizona, they found a $10,600 bill from their Internet provider - all because they had let their children stream movies on Netflix without realizing there would be roaming charges.

"The kids were getting bored," said Jason Gibson, in an interview with the CBC.  He had a so-called air card plugged into his laptop. And to ward off any whining, he let the children download "Shrek," "Curious George," and more, via cellular networks.

The only problem: when the Gibsons' children, Jayden and Sawyer, watched "Spider-Man," they downloaded about 400 megabytes of movie - at $6 per megabyte, since they were out of the country.

Their grandfather, John, was the one who first saw the bill. "He gave me a shout, told me about it, and my jaw hit the floor," Jason Gibson told a local paper, the Estevan Mercury.

This is not the largest cell phone bill on record.  Some others reported:

• There was a Florida woman last October who said T-Mobile charged her $210,000 in roaming charges on a trip to Canada.
• After the earthquake in Haiti, a FEMA employee from Maryland unknowingly ran up $30,000 in roaming charges in 2010 after she went to help with recovery efforts.
• There was an Illinois man who complained he was charged $27,000 for streaming a Chicago Bears game while he was on a Caribbean cruise.  (The Bears won and, after a nasty, drawn-out battle, AT&T agreed to void the bill.)

Julius Genachowski, the chairman of the Federal Communications Commission, has called for new rules to force wireless companies to alert consumers before and when they start incurring excess charges.

"Surveys show that 30 million Americans - one out of every six mobile phone users - have experienced bill shock, and it's a real problem that we need to tackle," said Genachowski in October.

SaskTel, the phone company and Internet service provider the Gibsons use, said it reduced the bill by $9,600 - though that means the family still got a $1,000 lesson on the importance of reading the fine print.  (Canadian and U.S. dollars are roughly equal in value at the moment.)

"We are finding that our customers are using an increasing amount of bandwidth," said Michelle Englot, SaskTel's director of corporate affairs, in an email to ABC News. "We have had some instances of customers exceeding the data usage that is included within their plans but for the most part, our customers do understand what is included in their data plans and it is not typically this dramatic."

"It is very important that a customer understands what is included in their plan," she said. "Also, we recommend that any customer who is traveling outside of Canada should turn off their data while they are roaming to avoid any unexpected charges."

Data plans in the U.S. are different, but not a lot different. And service providers say it is incumbent on users to avoid wireless roaming when they travel.

Jason Gibson said he would pay the reduced bill, but he isn't happy about it.

"I think when you plug an air card in and you're roaming, it should probably say you're roaming on it," he told the CBC. "Some sort of warning signal that you're not supposed to be using it in the States."