An aether server all by itself would probably not see enough use - probably end up like the voltz server. Additionally, it's not readily available in a launcher for 1.5.2 or anything newer. It is, however, a Forge plugin, and they give permission for it to be distributed in mod packs which sounds like it might fit into Famcraft's FTB server's private pack. However, it also claims to be incompatible with NEI. I'll give it a try this weekend hopefully. Perhaps the NEI incompatibility is just that the aether items aren't displayed in NEI.