If you want to read Japanese web pages, but your Japanese isn't perfect, you might be interested in jBrowse. It's a plugin for Microsoft Internet Explorer that adds furigana and word definitions to Japanese web pages. It's also a Japanese dictionary and kanji tool. It's also free, unless you pay out of charity. jBrowse can do four things:
1) Inject Definitions into a page in your browser
2) Add Furigana (explanatory kana) into a document that has hard kanji
3) Lookup Words -- it's also a decent two-way dictionary
4) Find Kanji by radical, stroke count, pronunciation, meaning, jouyou level, JIS number...

Platform: Windows NT, Windows 2000, Windows XP

System Requirements: There is no specific requirements