High speed internet question?

Okay. Here it goes... My friend has High speed internet access through AT&T. I just moved in with him and this other chick and we both have Apple computers. We are both still running 56k. QUESTION: If we are to buy a Ethernet Hub can we some how run his high speed internet connection to our computers as well? We (myself and this other gurl) have 10/100 Ethernet ports. Can we do this without the company finding out? Because I talked to a rep from AT&T the other day and they said they could do it, but it would tac on like 10 dollars (each) extra a month... HELP!