jeresig/fireunit

A Firebug extension for JavaScript testing.

sliminality/ply

CSS inspection aided by visual regression pruning

remy/jsconsole

Web based console - for presentations and workshops

LivelyKernel/LivelyKernel

The Lively Web runtime and development environment

SideChannelMarvels/Tracer

Set of Dynamic Binary Instrumentation and visualization tools for execution traces.

worrydream/Tangle

a JavaScript library for reactive documents

ivankra/javascript-zoo

JavaScript engines zoo

sokolovstas/SublimeWebInspector

Web Inspector allow you debug Javascript right in the editor