My worst nightmare was also a phone bill - $900!!! Not my cell phone ... my land line. Seemed that Ameritech wanted me to use my line for talking - not for fax or dial up. I said I never agreed to use my phone for talking only. They said they sent a letter of how phone was supposed to be used - loophole - the letter was sent AFTER I had the service connected. They tried to "discount" it for me and I held firm and said I was only paying for the regular monthly service (my dial up # was a local call). They finally agreed to remove those charges completely then said that I could no longer use my phone for fax or dial up - I said - nope. You can't sell me a service then change the rules on how I can use the service after I bought it. They left me alone - but it took SEVERAL WEEKS of phone calls to get it to stick. This was before we had cable in our town so there was no other option.
Now I don't even have a land line anymore. Vonage had a much better deal with monthly flat fee for all Long Distance INCLUDING to England and we call there a few times a week.