My upstream does not fully support IPv6 yet, so SixXS is awesome to fill that gap for me. I just happen to a developer on the Mono project, and SixXS gave me a chance to finally test our IPv6 support on the internet instead of just against my own private network. I'm also in the process of patching tons of bits and pieces of code I've written in the past to now support IPv6 now that I have something I can use. This project is the best! Zac Bowling http://zbowling.com/