What hardware devices (ADSL modems etc.) are IPv6 compatible?
The vast majority of DSL/cable modems and routers are not yet IPv6 enabled. Some can be made Ipv6 aware with a firmware update like OpenWRT, DD-WRT for the Linksys 54G router. Some ISPs like Comcast in the US and Free in France provide their proprietary modems, which are IPv6 enabled. Major router manufacturers like CISCO have already made software updates available for most of their router range to be IPv6 compatible. The Apple AirPort Extreme Docking Station also has excellent support for 6to4 tunneling.