This is also one of the extensions I can not live without, but I decided it deserves its own thread. This is a mouse-over Japanese dictionary for Firefox. Very useful when browsing Japanese websites or reading other Japanese text if you don't know all the Kanji.
- You'll have to install the base extension first, then one of the bilingual dictionaries. I think the Japanese-English one has the most comprehensive database.
- To turn Rikaichan on and off, you can click the rikaichan icon (a gray circle; becomes red when you turn it on) located in the status bar to the very bottom right corner. When Rikaichan is turned on, mouse over a word and it'll display the reading and meaning.
- Note that you'll have to place the cursor in the beginning of the word, since Rikaichan starts detecting words from the position of the cursor.
This extension is one of the reasons why I love Firefox.