A great deal of classical literature is available to read for free online, both in the original language and in translation.
Homer and Hesiod:
Aristotle:
Digital access to the complete corpus of medieval translations of the works of Aristotle.
Aims at documenting the various tools that were used in the Middle Ages for the study of Aristotle, with a special emphasis on Latin translations. Includes Greco-Latin translations in the printed Aristoteles Latinus series and also in some unpublished editions in preparation. Also includes the corpus of Latin translations of Greek commentaries and glosses on Aristotle (most of them published in the Corpus Latinum Commentariorum in Aristotelem Graecorum), texts that were closely associated with the Corpus Aristotelicum (such as the Liber sex principiorum, the Paraphrasis Themistiana or the Vita Aristotelis), and some translations from the Arabic (the Analytica Posteriora, tr. Gerardi and Averroes’Poetria, tr. Hermanni).