MorFix : Modern Hebrew-English dictionary and morphological-syntactic Hebrew search engine.
Gesenius' Hebrew grammar: Digitized versions on Internent Archive (download in different formats: PDF, Kindle, full-text); digitized in wikisource project Jewish Languages Research Website Modern Hebrew The Semantics of Ancient Hebrew Database
Yiddish Sources: Complied and mainted by Dr.Gerben Zaagsma, Department of Hebrew and Jewish Studies, University College London.
Yiddish-English-Hebrew Dictionary / Harkavy, Alexander: Digitized version
Yiddish Dictionary Online by Shalom Berger
Tools and Links
Hebrew Transliteration Tool : Transcribe a word or a text written in one script (e.g. Hebrew) into another script (e.g. English).
Lexicool: directory of bilingual and multilingual online dictionaries : The directory currently has links to over 6000 dictionaries and glossaries