This blog focuses on the ancient NE, distinguishing that from Classics; hence I don't often post sources of Classical interest. However, anyone who has ever had a chance to work with a Paulys encyclopedia knows what a fantastic resource it is. Moreover, there are occasions of overlap between the ancient NE and Classics.
This encyclopedia pertains to Classical studies, and is a Wikisource resource. As the title indicates, it is a German work. Those who do not know German will find help from Google Translator (which allows pasting of text to be translated); but despite what a great tool it is, users should be aware that the translations are not always accurate. For example, "Altertumswissenschaft" translates as "Classical Archaeology" (incorrect) rather than "Classical Studies" (correct). The translation does provide the option to check for alternative translations (click the translated word), but you'd have to suspect that a given word was inaccurately translated in the first place.