Called my cell phone and hung up when I answered

The DO NOT CALL registry is a waste of time.
I filed 93 complaints so far and it didn't make any difference.
Telemarketers ignore the registry as well as our requests to be
taken off their Call list.

This worked for me :
If you have a home computer, go to this website :
www.phonetray.com/phonetrayfree.htm
and download this FREE call blocking software for your PC.
Plug your phone line into the modem and add the offending number
to the "ZAP"list.

It will block over 65,000 numbers.
If there is no number, it can block by name, such as "UNAVAILABLE".
It will also block calls that are "allowed by law" : phone surveys, charities,
political calls, or companies with which a consumer has done business.
And it will also answer calls with a variety of messages; my favorite is :
"We do not accept telemarketing calls.
Please remove us from your calling list as required by Federal law".

I do not work for Traysoft - I found out about this software from another
annoyed individual.  It works as advertised and is FREE .