Help Requested: Dev-Related Tools & Plug-Ins?

[jjhunter]

I recently discovered that left-clicking/CTR-clicking in Firefox and selecting 'Inspect Element' opens up all kinds of magic for a baby dev like myself in terms of dynamically exploring a page's source code. What other tools or plug-ins do people use in Firefox, Safari, and/or Chrome for dev-related stuff?

Comments

[metawidget]

Wow, I didn't know that was there — the 3D view is pretty awesome (and useful, I think), too!