I haven’t investigated this to see if or what the downside is, but there are two websites that connect people who want out of contracts (and give away their phones) with those who want phones for free (plus the price of the contract). Be sure to read all the fine print, check what warrantee the phone has remaining and if it can transfer to you (if doing a iPhone, be sure it has Apple Care or you can still purchase it). Please email any experiences you have, positive or negative!

CellTrade (search for ATT, Apple for an iPhone)

CellSwapper (Search for ATT and look for an iPhone)