RFCs
RFC 1809, RFC 1881, RFC 1883, RFC 1884, RFC 1885, RFC 1886, RFC 1887, RFC 1888, RFC 1897, RFC 1924
Software
Networking, Debian GNU/Linux -- Debian IPv6 Project, IPv6 Software Resources, Linux + IPv6 HOWTO by Peter Bieringer, Microsoft IPv6, Microsoft IPv6 Technology Preview, Peter Bieringer's IPv6 and Linux, The Kame Project, Trumpet IPv6, Trumpet Software International IPv6
Tunnel Broker
AS8758 IPv6 Tunnel Broker, BTexact Tunnel Broker, CSELT, FreeNet6, Hurricane Electric, Free IPv6 Tunnel Broker, MANIS Tunnel Broker, Public 6to4 relay routers, The XS26 Project
Domain and Host List
This site contains a searchable list of IPv6 enabled hosts. You can add your own addresses.
HS247.com - IPv6 Links and Resource Site
News plattform with interesting IPv6 stories, links to the RFC's, the address space with maps and statistics. Contains also white papers, events and training with a detailed linklist for multiple OS implementations of IPv6.
Hurricane Electric - IPv6 Project Page
IPv6 project overview with free tunnel broker services and a IPv6 Forum. [Native IPv6, USA]
IPv4/IPv6 Address Information
Provides information about the IP address (either IPv4 or IPv6) that you are connecting from.
IPv6 Accessible Sites
List of public IPv6 based websites around the web.
IPv6 Essentials by Silvia Hagen
Sample chapter from her book and some background information about the book, which has been published by Oreilly. [PDF]
IPv6 Forum
World-wide consortium of Internet vendors aiming to promote IPv6. Includes mailing lists, event listings, technical information, and links.
IPv6 how-to
Short introduction to IPv6 and what you need to update on your side to make it IPv6 ready.
IPv6 Information Page
Resource site: how-to articles, FAQ, technical specifications, mailing list, details of IPv6-enabled applications, and links.
IPv6 Resources
Links to extensive IPv6 resources including RFCs, drafts, tutorials, papers, tools, router configurations, books etc.
IPv6 Tools
Many free web-based IPv6 tools, such as ping, tracert, reverse DNS, and WHOIS.
Klingon's IPv6 site
Offers useful web-based IPv6 tools, including a speed test, port test, and firewall test.
Native6, Inc: IPv6 Training and Consulting
Native6 provides training and consulting to help your company prepare for a transition to IPv6.
The IPv6 Mess
D. J. Bernstein explains how the current specifications make the transition from IPv4 to IPv6 a difficult one.