The folks who brought us the NET Bible have a beta site that offers several useful tools. (At least I found them useful.) By going to nextbible.org, you can view the NET text (with notes). Double-click on any word for a concordance. Click on a verse to compare to eight other translations, plus the Greek or Hebrew and LXX. Click on the KJV tab and get the KJV text along with the Strong's numbers. Click on the number to pull up the Strong's info. Click on another tab for the Greek or Hebrew with Strong's. Another tab takes you to the Treasury of Scripture Knowledge cross-references. Another tab provides links to articles on the Biblical book in question. There are several other features that I've only begun to explore. And everything is free.