Classical (Greek, Roman, early Christian)
Medieval (there is a separate page for Chaucer-related links)
Renaissance (there is a separate page for Shakespeare)
Restoration and Augustan (A site at San Antonio College, not by me)
18th, 19th and 20th century English literature (Not my periods, really)
British (& American) History and Culture
Art and Music (A cocktail)
Religion-related sites (Very limited)
Humanities and Computing (But many others offer more)
Supplementary literary texts (mostly medieval & renaissance) on my home page
The Oxford Book of English Verse, edited by Arthur Quiller-Couch in 1919.
World Cultures, at Washington State University.
The Alex Catalogue of Electronic Texts (fully searchable).