Hexago Inc.
Hexago is a leading IPv6 company that offers simple and cost-effective solutions for organizations wanting IPv6 capabilities in their Internet products or services.
Hurricane Electric - IPv6 Project Page
IPv6 project overview with free tunnel broker services and a IPv6 Forum. [Native IPv6, USA]
IPv6 Forum
World-wide consortium of Internet vendors aiming to promote IPv6. Includes mailing lists, event listings, technical information, and links.
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.
The IPv6 Mess
D. J. Bernstein explains how the current specifications make the transition from IPv4 to IPv6 a difficult one.