Maximum RAM

[paradigm]

I'm looking to create a little portable box (custom frame/case/whatever) that can be used to demo platforms and services, but to keep the weight down, I'm looking at going mITX (or at worst mATX).

Which mITX boards offer the most potential RAM capacity (not really bothered if AMD or Intel)? Is there anything in between the sizes of mITX and mATX?

I need a minimum of 8GB (which I know most mITX boards will cope with), but preferably I could do with 16GB, and I'm just not sure if that's possible?

 

[paradigm]

I've found some that claim to support 16GB, based on laptop SO-DIMMs, so I assume that 8GB sticks are available, although most likely very expensive.

Not going the laptop route as don't want/need a screen, and need the ability to have PCI/PCIe add-in cards.