Personally, I never suggest brokers. If I do, I'd feel responsible if someone signed up with a broker I suggested and got ripped off.
Not a lot of brokers carry CNY (Chinese Yuan, aka RMB, etc.). I do know that Oanda had it the last time I checked (please note that I don't have a live account with Oanda, so have no info on how good they may or may not be).
Of course, there is always "no leverage forex trading". Go to the airport, check the exchange rates for USD-CNY (or whatever your "home" currency is. Check it both ways, since you want to find the spread. If you see someone heading to the conversion booth with a fistful of Yuan, make them an offer that's 1/2 between the buy and sell rates of the money changers. You benefit, the person selling the CNY benefits, and you can probably get away before the money changers send airport security after you (if you are quick).
Personally, I keep nice pile of RMB on deposit in my multi-currency account at Mattress Bank.
Mattress Bank - protecting your assets since 1929.
I need to update that article. I sent some followup questions to a BOC manager, and am told that they now they only carry art bars with a significant markup. I'm currently re-checking prices and delivery options at a couple of other banks, and have a line on a silver supplier.
For those of you wanting to annoy airport money changers, make sure when you go after Chinese currency that you get the money from the People's Republic of China - that's the currency that could be appreciating in value soon. Check this link to see what the current series of RMB/CNY looks like:
The quickest check for counterfeits - run a fingernail against the weave of Chairman Mao's suit nearest the corner of the bill. The ink on a real note is raised, so you'll be able to feel the texture. Simple color copies will be flat and have no texture. Also, never accept a 100 RMB note with a serial number beginning with HD. There were a bunch of very high quality counterfeits that started with that serial number.
you can also buy a maximum of 20 000 RMB per day at a Taiwanese bank. You can also buy gold coins and bars at some branches, like the bank of Taiwan branch near Taipei Main Station. Here's the price list, in NTD.