IPv6 scoped addresses

Link-locals
necessary for operation, and in some cases very useful
Site-local unicast/anycast
using site-local anyast for DNS server discovery
using site-local unicast for IBGP peerings
we can live *without* them and have not seen real need, though
no experiences on multi-site node
Scoped multicast (other than link-local)
in use for multicast streaming
experimentally tried for DHCPv6 and router renumbering
do not have an essential reason for narrower scopes