Firefox 3.0’s new default Mac theme showed up today in the current trunk nightly (Minefield). The theme is very similar to Safari’s.
A bunch of animated gifs are worth a thousand words.
The sources for NCSA Mosaic v2.7 — one the first graphical web browsers (1993) and certainly the one that led to the World Wide Web as we know it — can now be found on GitHub.
You can even run it on a modern Linux. Here’s what the GitHub homepage looks like:

The team that built NCSA Mosaic (Marc Andreessen et al) would go on to create Mosaic Communications Corp., which eventually became Netscape Communications Corp., which open sourced the Mozilla browser, leading to Firefox.
I wonder if any of the original NCSA Mosaic code still exists in any form at mozilla.org.
The Mosaic Wikipedia entry has a thorough history.
Oh, nice. Here’s a high-level design document that describes the new cross-site XmlHttpRequest (their calling it, “XXX”) functionality and ties the other documents floating around out there together. It seems that servers will be able to signal that certain resources are accessible from other domains using HTTP headers or (gasp!) XML processing instructions (PIs). Weird.
Just landed on mozilla trunk a few days ago. See the draft spec for specifics.
Awesome. I didn’t even know there were such things as Firebug Extensions.
“This plugin will alert you if you accidentally stumble onto MySpace.com, and take you back to the site you came from.”
“Code Rush follows the people of Netscape Communications during an intense period in 1998, when it was all but certain that Microsoft had already won control of the Internet user’s desktop.”
“… anybody who’s ever built out a relatively complex design using ems will agree that at some point they wondered if the benefit was really worth the effort.”