Question about buying unlocked cell phones on Ebay
 

What does unlocked meen? I have cingular so i can buy any phone that accepts cingular and just plug my sim chip in and it will work? I don't have to call cingular or anything?

yes, you need to have Cingular activate the phones serial number on your acct

if the phone is unlocked you can buy any phone that accepts a sim chip and it should work fine w/ your sim

if its unlocked you can just pop your sim in and get it working
i am using an unlocked cingular phone right on rogers right now

That's only for CDMA phones, not GSM.