几个能用的 NAT64/DNS64 Service

http://aa.net.uk/kb-broadband-ipv6-nat64.html:

To use the NAT64 gateway simply set your DNS resolvers to
2001:8b0:6464::1 and 2001:8b0:6464::2. We no longer provide an IPv4
resolver due to abuse.

http://ipv6.lt/nat64.php：

nat64.litnet.lt (2001:778::75) - serveris atliekantis NAT64
transliavimą krioklys.litnet.lt (2001:778::37) - DNS serveris
atliekantis DNS64 funkciją 2001:778:0:ffff:64::/96 - IPv6 NAT64
prefiksas
193.219.61.0/24 - IPv4 NAT64 prefiksas

http://www.trex.fi/2011/dns64.htm：

nameserver 2001:67c:2b0::4
nameserver 2001:67c:2b0::6

下面两个好像失效了：
https://go6lab.si/current-ipv6-tests/nat64dns64-public-test/
http://ecdysis.viagenie.ca/ietf79_network_experiment.html