This is Jinwuxing, which some rumor to be the biggest swap meet/public market in the world. It's amazing, and the telecom store inside is the best place to get IP cards or cell phones (bargain for the latter, they'll give u a good deal). All my telecom shopping is done here, but please don't pay the embarassingly huge amount I did for a pair of shoes here...they're worth about 5 bucks on average, price accordingly.
EAP China! Robert Klein