The domain, which titles itself as an "@Anywhere test site", asks you to connect to Twitter and shows your following status for @Ev, @Biz and @Jack, Twitter's three cofounders. You can also view a hovercard for @wendyverse, Wendy Hepworth, no doubt part of the family of Isaac Hepworth (@isaach) who joined the company via Google.
Connecting Via Twitter @Anywhere
Showing Following Status with Ev, Biz and Jack, as Well as A Hovercard
It's not a fancy site, but it works. The raw code gives a hint at what is to come as Twitter extends @Anywhere and you see this information flow through the rest of the Web. Test it out yourself here: http://eggboiling.com/