Grothendieck's "La longue Marche à travers la théorie de Galois"
This article from Le Monde (in French) and this blog (in English) are recent and seem to accurately sum up the state of affairs: In April 2012 Jean Malgoire (see the video interview in the blog) donated the manuscript of "La longue Marche" (700 handwritten pages written by Alexander Grothendieck in just 20 days in 1981) to the library of Montpellier University. They have announced on 17 June 2015 that they will digitize the manuscript (and other documents from A.G.'s estate) for purposes of conservation (apparently the text is fading). Distribution can only happen after permission from the heirs. No indication that this will happen anytime soon.
An earlier MSE posting indicated that one can write to prof. Malgoire to obtain transcriptions of "La longue Marche". The relevant web page was removed in 2007 (it survives in this archive), and I presume the present legal situation regarding the estate of A.G. would prevent any such informal dissemination (beyond what is already available at the Grothendieck circle).
All the manuscripts have been finally made avaible by Montpellier university.
You can find all of them here, avaible in pdf.
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