I was reading this article called Twenty Five Little Known Telephone Tips for Private Investigators and when I read tip #16 I decided to give it a try so I called the first number which is to the MCI Network and MCI's Network said that their Caller ID said that I was calling from number (214) 446-0482. So I hung up and called right back and this time the MCI Network gave me my correct phone number. So I waited a couple of hours and called the MCI network number again and again their Caller ID said that I was calling from (214) 446-0482 I hung up and called right back and again I was given my correct number again. I have pasted a copy of tip #16 below.

"Know The Number You Are Dialing From" Tip Sixteen:
These are known as ANAC numbers which are used by telephone repair people. Here are some national ones certainly reported. 800-444-4444, 888-324-8686, 800-444-3333, 800-727-5207, 800-555-1160.
 Nov 29th, 2007
i called it also it says disconnected as well. so I called the operator they said it is a tele-marketer...dialing by a computer and the reason it hangs up on you is that it calls more than 1 person at a time........so just ignore it next time they call
 Oct 25th, 2007
This number called only showed Dallas, Tx and then hung up. When I called back there was a recording that said this number has been disconnected. VERY STRANGE.
 Oct 23rd, 2007
Have no idea who this is?? anyone??
 Oct 22nd, 2007