It also has no moving parts and you can swap out the SD card to a spare quite easily. It's not something for an enterprise environment, but as a hobbyist, it's an awesome thing for the cost.
I'm moving most of my stuff to the dedicated servers on DCs, so the only thing I need at home is basically bulk storage, networking, misc stuff... a local IPA replica is overkill (as having IPA for home is, I guess), but it would be nice to be able to have a NAS and a Raspberry and be done with it (I'm currently running a Proliant Microserver, though).
Are there any issues running FreeIPA on the Raspberry, other than the low memory? IIRC, CentOS 7 now has a compatible ARM build...