Here's a couple of freeware goodies that might come in useful.
1. Freelang Dictionary
This is a free dictionary you can download and it comes in several languages. It's a bit basic, (romaji only, no kanji), but it can come in handy. The fact that you can use the same soft for multiple languages is good.
http://www.freelang.net/dictionary/index.html
2. IESpell
This a spell check you can use for webmail, forums, etc. Just right click and select Check Spelling. Works on IE based browsers.
http://www.iespell.com/download.php