By 'permadeath' I'm assuming you mean that once you die, you lose your character, but please correct me if I'm wrong.
It gets mentioned occasionally, but I'm not sure if there are any servers like this running right now. There might be some, I just don't know of any off the top of my head.
I'm working on a PvP server where players will return to level 1 and lose spells, skills, equipment, etc.. when they are killed by opponents (strictly in PvP, not PvE). (
http://cohpvp.net/?page.cohpvp-information)
I think this type of gameplay has the potential to be a lot of fun if done properly, the only problem is that most people do not want to invest many hours into a character knowing they can lose it all in an instant, especially considering the transient nature of many Emu servers.