Rather than adding to this thread about SIM cards, I'm starting a new thread now because the scope of our communication options/needs has changed a great deal during the course of the past 2 years.

While casual tourists should be able to get by with a simple SIM card purchased from a newspaper stand, anyone who makes multiple trips per year and/or plans on spending a lot of time doing ground transit should book 2 hours early during their trip in order to go to an electronics market; I'm not talking about Dazhong Dianqi or its peers; you need to get local!

This is fresh in my mind because I did the entire drill just yesterday for a guest who requires 24/7 access to Bloomberg. Here are my tips:

1) when you enter the market, you will encounter many people who want to help you buy
*I used to think "screw that"; I can get better prices if I shop for each item individually
*but, I've come to realize that having one person take care of all of my needs saves me a considerable amount of time, plus I get to hold him accountable if anything breaks... well worth whatever kickbacks he receives
*just try to pick a person who looks friendly, probably not on the first floor of any given market

2) the wireless router
*single best purchase I've made during 2012, to date
*Unicom WCDMA is the fastest, and also the most expensive in terms of data pricing; having used (very slow) China Telecom in the past, I would not think twice about paying the Unicom premium (we're not talking about big bucks here)
*the Hame router, for which I paid y600, now costs y450, and the Huawei router is y700; my guest went for the latter because the merchant told us it was a better brand

2a) WCDMA SIM cards
*as far as I can tell, they don't have phone numbers attached to them, and your iPhones don't support them anyway, so if you buy one, think about data only
*data costs y80/gig
*the y300 cards sell at face value, and last for 6 months
*the y1200 cards sell for y900, and last for one year
*there is a minimum monthly usage charge

3) SIM card for your phone
*if you have a smart phone, Unicom is probably the way to go because very few non Chinese phones support China Mobile 3g
*3g Unicom SIMs cost y150, including y50 in credit, though I've heard you can knock the price down to y100

4) spare phone
*if you have an iPhone or similar, you should pay y50 to jailbreak it so you can use it with your new Unicom SIM
*but, if you don't want to miss calls to your Verizon number, you should consider picking up a spare phone; a pretty decent base level Nokia will set you back no more than y250 (y150 if you want go really, really ghetto)

5) universal USB charger
*these cost a mere y20, and can charge pretty much any mobile device under the sun via your computer's USB port

6) travel router
*many hotels in China don't offer in-room wifi, but you can solve this problem by purchasing a travel router (plug it into the wall socket, and connect it to the ethernet port)
*cost = y120 (sure, Fry's and Amazon might be cheaper, but since you're already in the electronics market, why not pick one up?)

7) headset with microphone (self-explanatory; they are cheap, and will permit you to use Skype/gchat with less "are you there?" moments)

8) configuration of devices
*before you leave the market, implore your "guy" to make sure that everything works, sets your SSID/password to terms of your choosing, and changes the software interface to English (not always possible)
*be sure to get his business card

9) haggling
*I encourage you to try your best on this front, but don't expect any miracles
*20% off on certain products is doable; for low margin items, you may well be stuck with their listed prices

10) market locations
-per jiejie's suggestion, I'm adding this section here, which I will try to keep updated based on user suggestions
-Beijing
*I can't recall the name of my favorite market, but it is half a block north and half a block west of Chef Too; I will try to update this later
*Buy Now: This is a little more expensive than the aforementioned location, and traffic in the area can be intense; I prefer the newer complex on the northwest corner over its sister across the intersection
*Zhongguancun: Generally cheaper than both of the above, but more time consuming because you need to make the trek up there, and it is extremely massive
-Shanghai
*Xiangyang Electronics Market
-Shenzhen
*Hua Qiang Bei: sort of like Zhongguancun on steroids
*Since Shenzhen it takes an hour+ to cross town in Shenzhen, and electronics are the lifeblood of the city, I recommend finding a smaller market close to where you happen to be; all districts have them

Great rundown and great idea to get one person at the market to chase everything down. One suggestion: add to above, the hanyu pinyin and hanzi for each item (nouns), so somebody with some Mandarin skills can deal with market themselves rather than require a helper to go along.

And mnredfox can hopefully put a link to this thread in the master FAQ sticky.

Might also be a good idea on this thread, to put names and locations of best electronic markets for each of the major cities travelers are likely to enter in (BJ, SH, GZ, SZ).

Great entry md. However, being the luddite that I am, what are items 2a and 2b? Are these similar to a mifi? Do I need one (odd question I know, since if I don't know what it is, how can I be missing out!). I take it that this is more for visitors that don't have a data plan...in which case, more than happy with my unicom prepay data plan and my samsung.

tb

I don't know the technical term for it, but it's basically a wireless router. There are several different varieties; the guys at the computer market tell me that Unicom WCDMA is the best, and I have no reason to dispute this claim (China Telecom is NOT good on the train).

Many smart phones have tethering functionality, but having a dedicated router tends to permit slightly better performance.

On a related note, my balance hit zero this morning so I decided to go to the Unicom store in order to recharge. In retrospect, this was a HUGE mistake; one should never, ever set foot inside a Unicom store!; either recharge at the bank (you need to know the "phone number" attached to the card in order to do this), or simply buy a new card... same price as the recharge.

Wireless routers are what you have in the home to convert your ADSL/cable internet signal into wireless. Sounds like what you are describing is as trueblu referred to as "mifi" or mobile broadband, where the SIM card is inserted into a USB internet dongle, and you can connect your laptop to 3G/broadband services.

No. My device looks kind of like a cell phone. I can leave it in my laptop bag or my coat pocket, and still use it, as can up to 5 other people.

I think the marketing/industry term is mobile hotspot (or mobile wifi hotspot).

On #6, that is something one can buy stateside before leaving. I bring along an Airport Express, which is preconfigured to provide access through the ethernet port in the room. The advantage is it's password locked, so it's as secure as the ethernet in the room (as opposed to hotel/public wifi).

Ok then it's a mifi or mobile hotspot as others have called it. Definitely not a wireless router though.. That's something else completely different.

I need one of those actually..

I noted this in my OP; both Fry's and Amazon can crush the Chinese in this product area, but we're talking about a $2 price difference. When I lived in Portland, the drive to/from Fry's cost me $4 (and, I actually had to drive). Basically, if you already have a travel router, you are good to go. Otherwise, picking one up in China along with your other goods would not be a bad idea.

There seem to be more options for 2a depending on where in China you are. These are two Shanghai-based options I got.

1200RMB card (the shop I bought mine from wouldn't discount off the price of the SIM, but was willing to throw in a mobile hotspot or USB modem for free) with local pricing:

96RMB/month for 3GB Shanghai-local+500MB out-of-town or 3.5GB Shanghai-local

Prepaid card for local use:

300RMB for 9GB/3 months

Once cut to microSIM size, they also work in iPhones for data and text, but not phone calls.