Optronics(For Japanese only)

The lens dictionary & encyclopedia of an optical industry journal
http://www.optronics.co.jp/lens_jiten/?PHPSESSID=d9eb716743760fbfc75e623aad054c2e

Wikipedia

The free encyclopedia
http://en.wikipedia.org/wiki/Main_Page

Yahoo! education

Easy-to-use online dictionary
http://education.yahoo.com/reference/dictionary/

yourdictionary.com

English-English dictionary online
http://www.yourdictionary.com/

weblio dictionary(For Japanese only)

Search across a variety of dictionary
http://www.weblio.jp/

Visual Basic Junior high school(For Japanese only)

Beginner-friendly website
http://homepage1.nifty.com/rucio/main/main.htm

radiko.jp(For Japanese only)

Internet radio
When boiled down to various…、it hears and refreshes also with -- and radio!
http://radiko.jp/