Online  Bibles -

http://purl.org/ECanon -   E-canon currently has: 

• King James Version (KJV)
• Revised Standard Version (RSV)
• New Revised Standard Version (NRSV)
• Westcott and Hort Greek New Testament (unaccented) (WH)

Online Parallel Bibles

http://www.bible.gospelcom.net/passage/  - click on passage lookup

http://bible.crosswalk.com/ParallelBible/

 http://www.OliveTree.com/cgi-bin/EnglishBible.htm (By holding down the control key, you can add and delete Bible versions)

If you are looking for Greek texts as well as translations in a number of languages, check http://unbound.biola.edu/index.cfm