Anyhoo ... to start the festivities, I've got a couple of websites for you (which I may have mentioned before). The first is the Library of Ancient Texts Online (LATO), which boasts itself to be "the internet's most throrough catalog of online copies of ancient Greek texts". It doesn't actually house those texts, but links to them. A good one to bookmark alongside David Camden's Corpus Scriptorum Latinorum site.
The other site I wanted to mention is actually a book ... its Vitruvius' Ten Books on Architecture as translated by Morris Morgan (1914).