Up-to-date online versions of:
The Grove Encyclopedia of Classical Art and Architecture
The Oxford Classical Dictionary (3d rev ed.) Reference library
The Oxford Classical Dictionary (4th ed.) Reference library
The Oxford Companion to Classical Civilization
The Oxford Companion to Classical Literature (3d ed.)
Oxford Dictionary of the Classical World
The Oxford Encyclopedia of Ancient Greece and Rome
Pocket Oxford Latin Dictionary: English-Latin (3 ed.)
Pocket Oxford Latin Dictionary: Latin-English (3 ed.)
Who's Who in the Classical World

http://www.oxfordreference.com/browse?t1=ORO:AHU00670