The Center for Hellenic Studies has just announced an ambitious project:

First Thousand Years of Greek

Making first an inventory of all Greek texts transmitted by manuscripts, which is already a Herculean task, but still more they also plan to create a full corpus of these texts and to make them available, at least in one version attested by manuscripts.
It is not worth saying how interesting such a project may be, but it is also remarkable that their corpus will be open for collaboration first, for usage second.