and this and this, and then i got my husband, and i said allen, something is wrong. reporter: for the price of bob st. germane s bill, he could have bought a new car. $18,000 of data charges when his son went online. theirs are extreme cases, but millions of others have experienced some form of what s called bill shock. it s even caught the attention of fcc chairman julius general cow ski. how big a problem is this? our survey found one out of every six mobile subscribers, 30 million people, have had some form of bill shock at the end of the month. it s obviously a very significant problem. reporter: the fcc is proposing what it calls a simple technology solution, mandatory warnings from the cell phone companies, whenever a subscriber runs up an oversized bill. before you go over the limit, you can get an alert, a text alert, a voice alert, from your mobile company, saying, hey, you re getting close to the limit. reporter: some lawmakers want to take it a step further.