This is an, as yet unmerged, fork of this: https://addons.mozilla.org/en-US/firefox/addon/selenium-ide-sel-blocks/

Chris Noe's SEL-Blocks provides many additional looping and conditional commands for your Selenium automated testing scripts.

This unacknowledged fork adds a JSON data source capability, in addition to the XML stuff in the original.

Update 2013/08/03 : - Added a new function loadJsonVars that allows loading key value pairs into storedVars from a JSON file. Test scripts updated too

NOTE : Many thanks to Brian Hanna for bug fix, last May.