Public Teredo servers:

• teredo.remlab.net / teredo-debian.remlab.net (Germany)
• teredo.ngix.ne.kr (South Korea)
• teredo.managemydedi.com (USA, Chicago)
• teredo.trex.fi (Finland)
• win8.ipv6.microsoft.com (The Teredo server hidden in Windows RT 8.1) of which Windows 7 has no knowledge.
• win10.ipv6.microsoft.com (Window10 default server)