Hosted by the École normale supérieure in Paris.
Hat tip: Continental Philosophy
This is now on my Favourite Sites section
Looks like an essential tool for everyone working on Nietzsche. Giorgio Colli and Mazzino Montinari German language editon of the Collected Works online and searchable, and facsimiles of original manuscripts. The last aspect may not be working very well at present though, I opened specimen pages with Safari and Firefox browsers, but could not see any text.