This is what my current architecture looks like (in my mind, at least):
I already got a NAS (a Synology DS211, which is great btw) up and running at home and there is also the embedded linux controller. It is a bit redundant to have two devices running parallel, but the embedded linux box is a really low power one, running 24/7 consuming only 2-3 Watt while the NAS takes 20W and currently shuts down at night to save energy.
I have not yet finally decided whether the home automation stuff shall run on the one or the other device. I just started with the embedded board, as it runs a standard (ARM) debian distribution and i just needed some shell skripts and dont have a SQL integration yet. Maybe i'll also set up a toolchain for the NAS system to deploy the automation software there. But before doing that, i need some more sensors.
I think i makes sense to first add some sensors and monitoring software to see if the systems runs stable. After all, its a pretty complex setup involving many components. And any failing component would be a show stopper.
As the next steps i plan to monitor the temperatures, lightlevel and motion in all rooms. I also want to add a humidity sensor to the bathroom, maybe also the other rooms.
Therefore i just ordered some JeeNodes from Jeelabs. I still have some RFM12 units and sensors in my box, so i plan to start building more sensors based on them.
