zkanji - zkanji is a free and open-source study tool and dictionary of the Japanese language.
Takoboto - Japanese dictionary & Japanese language learning tool.
Jisho - Powerful and easy-to-use online Japanese-English dictionary with words, kanji and example...
Rikaichamp - Look up Japanese words with the hover of a mouse.
Akebi Japanese Dictionary - Offline Japanese-English kanji dictionary.
rikaikun - Translate Japanese by hovering over words.