Classics

• Thesaurus Linguae Latinae
  Open Access!  The largest dictionary of the Latin language in existence, begun in 1894 and continuing today.  The dictionary focuses on Latin from 600AD and earlier.  This open version includes PDFs of print volumes to date.  
   
• Ancient World Online
  Blog providing up to date massive quantities of links to new Open Access digitized content.  Also available (syndicated) through Facebook & Twitter.
   
• Biblioteca digitale di testi latini
  ​Chronologically follows Phi Latin, currently covering "pagan" texts, with free use and downloading.
   
• Corpus Medicorum Graecorum
  Berlin-Brandenburg Academy of Sciences and Humanities
  Galen of Pergamum and others
   
• Open Greek & Latin
  "An international collaboration committed to creating an open educational resource featuring a corpus of digital texts, deep-reading tools, and open-source software. [striving] to support and enhance teaching and research. All materials can be downloaded, modified, and redistributed in accordance with all applicable licenses."
   
• PHI Latin Texts
  Packard Humanities Institute
  Open Access! Searchable classical (and later) Latin texts

• Perseus texts
  Primary sources (major texts) covering  the history, literature and culture of the Greco-Roman world.  All texts and materials believed to be in the public domain are available for free download.

• Perseus Advanced Search with PhiloLogic
  Largely from the Perseus corpus, “The Greek and Latin texts are richly encoded for content rather than form (e.g., not page breaks, initials, and indents, but speaker information, metrical information, and milestones). The Perseus site is further enriched by intricate linking mechanisms among texts (resulting in more than 30 million links).”

• Library of Humanistic Texts (University of Birmingham, UK, Philological Museum at the Shakespeare Institute)
  Full-text collection of critical editions (frequently with translations) of a large number of 16th and 17th century texts. It is created and maintained by Dana F. Sutton, University of California, Irvine. 
   
• Bibliography of Neo-Latin Texts on the Web (University of Birmingham, UK, Philological Museum at the Shakespeare Institute)
  Analytic bibliography of Latin texts written during the Renaissance and later.  Freely available to the general public on the Web, and created and maintained by Dana F. Sutton, University of California, Irvine.

• Logeion provides simultaneous lookup of entries for ancient Greek & Latin words in the many reference works that make up the Perseus Classical collection.  A simple word look-up is supplemented by information based on corpus data in the right side bar, as well as references to chapters in standard textbooks.  Standard works include historic versions of Liddell-Scott and Lewis & Short.  

Attic Inscriptions Online (AIO): 
The core of the site comprises annotated English translations of Attic inscriptions. The most popular means of accessing a translation is via browse by source. If you browse by an outdated reference (e.g. an old edition of IG) you will always be led to a translation of the most up-to-date Greek text. Each translation includes a link to the Greek text translated, whether on an external site or in many cases on AIO. AIO's policy is to include our own Greek text of an inscription where no up-to-date text is available online elsewhere in open access. Every translation also includes links to any available online images of the inscription, on external open-access sites or on AIO.