Read Bob Rankin website and check his list of free reference and Web research tools.
You will find both web resources (encyclopedia, dictionaries etc) and tools. The list lacks of typical Web research or Web clippings tools (Evernote, Webnotes, Zotero, Ubernote etc) but you will find Web resources in different sectors, e.g. medical advic e, business and financial research, language translation, movies, music, genealogy, US government etc.
У автора очень приятный слог