Hi, I'm one of the project linked to by Scribo. I just wanted to make a quick correction to his kind note: Perseus' digital library of TEI-encoded XML ancient texts come with the most liberal users' rights imaginable. In fact, this collection has been very helpful to us in 'seeding' our OCR process. In turn, where our raw OCR results complement the existing PDL collection, new XML Perseus editions are being created by hiring OCR editors at a far lower cost than double-key entry. My partner in this endeavour has devised a OCR editing environment ideal for ancient Greek.
It is the TLG which constrains users' rights considerably, and has enforced these through threats of legal action.
Finally, beyond the purview of either of these projects are the monographs, articles and educational works that comprise polytonic Greek. What teacher of intro Greek doesn't relish the possibility of cutting and pasting from, e.g., this page at this time of year:http://heml.mta.ca/lace/sidebysideview2/11258875
Federico and I encourage people to submit requests to this spreadsheet:https://docs.google.com/spreadsheet/ccc?key=0ArJt01185Q8mdERsS2VRMngtTWRNUDAtNGFxZXhFQVE#gid=0
Bruce Robertson, Head of Classics, Mount Allison University