If you want to read Japanese web page, 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:
Inject Definitions into a page in your browser
Add Furigana (explanatory kana) into a document that has hard kanji
Lookup Words -- it's also a decent two-way dictionary
Find Kanji by radical, stroke count, pronunciation, meaning, jouyou level, JIS number...
System requirements:
Windows NT/2000/XP, Internet Explorer 5.5 or above, Japanese font