Ever consider Seeed Studio? We have just refreshed our stock along with NKC electronics,
http://www.seeedstudio.com/depot/freeduino-usb-complete-kitarduino-duemilanove-compatible-p-58.html

We have customized some long pin female headers for whoever wants to make shields.  

http://www.seeedstudio.com/depot/female-shield-stacking-headers-6-pin-100pcs-pack-p-222.html

http://www.seeedstudio.com/depot/female-shield-stacking-headers-8-pin-100pcs-pack-p-223.html

IMHO, A photo would be great... before you clean it up.

For mass production, it is very neccessary to discuss with supplier on these details, even specify the solder used or demand an extra cleaning process.

For small batch manufacturing, the factory uses hand soldering. As far as I have seen, there are 3 most popular flux:
1. the yellow solid one, which would probably leave many messy to the soldering point, most difficult to clean (chemical solvent).  
2. Light yellow solid one, it leaves flimsy white residue after soldering, even your finger nail could remove them easily.
3. Light yellow fluid-like, it leaves some oily residue, a tissue will remove it perfectly.

The third one is the most expenisve, but the final result is only on visual part. They all contain flux, cleaned away or left messy.  

We store FT232RL, and small qty is welcomed  

If you are interested in build one yourself, jym has contributed us a open source PCB here:
http://www.seeedstudio.com/forge/wikka.php?wakka=Arm9DevBoardjym

[What's RainbowDuino?]

What's RainbowDuino?

A valuable duino with extensive control capacity, for quantity project usage. Estimate price  $8-$15

Features:

No on-board USB-UART chip -  Trimmed for cost reduction,  Separate UartSB or wireless module will be provided for USB connection.

MCU to be mounted - Program offline and plug in, you may also choose any compatible MCU you prefer to use.

Extensive Control capability - Multiplexed I/O port with 74HC595 [ch65288]or more integrated bi-directional ICs, suggestion welcomed)

Easy Cascade - Specially designed I2C port,  DC in& Out,

Applications:

Control over LED matrix or Robotic.

Pending for suggestions.

1. Is there a inexpensive IC more powerful than 74HC575? Maybe Bi-direciton multiplexer with more channels.

2. How about more UART?

3. How about CAN?

Thanks for any suggestion or concerns ^^

We are looking to host some open source shields, check it out: http://www.seeedstudio.com/depot/propanganda-pcb-service-for-open-source-pcb-p-111.html  

We carry a few sensors, some more will added after Oct.6th including the distance IR sensors.

IMHO, the great thing about open source hardware is that -- people may choose whatever they like, or create one if no choice fits.

 

So this is a unreleased version of Freeduino?
I2c... I'm thinking about the empty space now, it's a good idea

The PCB has arrived~  



More details will be added. http://www.seeedstudio.com/blog/?p=39

Why is C8 a through-hole?  You should get rid of the thermals on the voltage regulator, because you WANT all that copper to act as a heatsink.  The power connector looks "flimsy."

Thank you Westfw!

C8 is an optional capacitor, it is from FTDI reference circuit and we wanted to keep it for further use. People may want to hand solder this one on to improve FT232's 3.3v power output.

For the heatsink, maybe it's already big enough like this? It's much easier for solder the regulator, and you may solder bridges to expand the heat sink.

The power connect is not a DC jack but 2-pin plug. We thought it would be easier for batteries, and a simple converter will suit it to power adapters.

We are not sure if these changes are positive, your concern warns us to think it over again. The PCB is sent for  manufacturing, expect to have it ready on Sep 14th, I will post some photos for comments!

[another]

Thank you guys for these valuable suggestion!

- ICSP will be back...: )

...
it's becoming a forest of connectors

- Some headers may be left  unsoldered by default[ch12290]  :

It seems to me that you have a whole lot of headers that weren't on the original arduinos so, correct me if I'm wrong, maybe it can be interesting to find a solution for bypassing the FT232 and replacing it with an ATtiny running AVRUSB for those who want it. I was thinking a small switch of some sort (or jumper) on the VCC/VCCIO of the FT232, and a header allowing easy access to the D+/D- pins of the USB socket. I might be saying crap ^^

- We were seriously considering about the way to bypass USB chip. It would increase complexity further about the board, Maybe it would be more conveniet if people equip another USB jack with ATtiny or else? Please correct me if I have ignored some important factor.

My bet is that this board is going to be one of the best for those who want to hack the arduino itself... ^^
Speaking of headers and connectors, wouldn't it be neat to have a socket for the ATmega? This way, it will be easier for a lot of us to program the chip and move it to a standalone design. Ok, you can do it via ICSP, but this way you would not have to bother implementig ICSP on you target board. And it will be easier for the people who burn their megas (seems to be a lot lately ^^)

- Thank you for the comment, it's always encouraging! ^^ I will source for the suitable socket first, it's too expensive to use test sockets. If it's making things more complicated - a later Giganic Super Powerful one might include this...  

Check this out ;D



Larger file http://www.seeedstudio.com/depot/images/product/seeeduinoPCB.png
Scheme: http://www.seeedstudio.com/depot/datasheet/seeeduino.sch

Brrrrravo~~~
Thanks again Melka! >