Amia is a Neverwinter Nights persistent world roleplay server that became active in December 2004 after a split from the Arelith server. Because of this it has a long and colorful history dating back pre-HotU.
The server requires both Shadows of Undrentide and Hordes of the Underdark to play and has a level cap of 30.
The main developers of the server were Jpavelch, MagnumMan, Kungfoowiz, PaladinOfSune and Disco, although of these only the latter two are still active. Amia also has a multitude of designers and testers in addition to the Dungeon Masters (who may themselves also be developers, designers and/or testers), making the server very much a team effort.
Amia is currently spread across two servers, with a maximum capacity of 130 players.
There are also no class restrictions whatsoever, although it does have changes to the Monk, Shadowdancer, and Red Dragon Disciple classes. Additionally, there are changes to virtually all spells and other parts of the standard game engine.
Amia has recently altered a longstanding policy of no haks and has now added a hak-pack, which is required to play on Amia. You can download the files needed here