I've been thinking of building Linux From Scratch [1] as an effort to better understand the workings of GNU/Linux. Would this be a good machine to build it on? It certainly seems to fit the bill!
I'd do LFS in a VM first. If you try doing it on one of these devices, then either you're cross-compiling (which can be somewhat finicky), or you're compiling on this device (which will be slow).
I would try it on an x86 device first, just to get your feet wet. There's enough ways to trip yourself up with LFS without trying to do it on unusual hardware.
[1]: http://www.linuxfromscratch.org