I absolutely love repurposing these thin clients for such an useful thing. But it is quite challenging to add a 2nd hard drive to these. Unless you can get an SSD PCIe card with its own storage controller, I'm afraid that your options are quite limited.
Here's an idea: You could add an actual, separate storage controller for the mini PCIe slot and add a very thin SSD drive:
Just make sure that you insulate the SSD with a sheet of plastic or cardboard, if it fits.
That's a full height pcie adapter, maybe it's gonna fit but then I have to remove the clamp on the motherboard and make a new one to serve full height. There is some space left for it.
And the thing doesn't supply power.
So of the half size msata ssd so t work, no problem at all. It would be nice to use the capability if possible.
Maybe it's better to find the http://www.amazon.com/gp/aw/d/…=1407647271&robot_redir=1
Expansion module kit but most of the are listed in the USA, so shipping is around 2x the price of the module itself and 3x the price I paid for the whole thin client...if someone has closer contacts who sell these thing let me hear! (uk / Europe )