This extension turns a cube when changing between tabs. Useless, but oddly entertaining (and slow).
Worth installing/uninstalling just to see, IMHO..
Link: Tab Effect
via email: thx tim!

Link: Making of
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Remember the guy who installed 100 Firefox extensions and still had a stable browser? Old hat.
I'd hate to wait 6 minutes for my browser to start though.
Link: 200 Firefox Extensions Installed At One Time!
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Even though I have the RSS feed for new extensions, I just realized I haven't been paying attention.
It's been about ten months since this list was updated.
Firefox has updated several times, and each time, extensions have become obsolete, and I've just gone on without 'em.
Thanks to this post, I finally did a little introspection. Yeah, I'm slow.

Currently installed:
All-in-One Gestures 0.17.4
Answers 2.1.12
BBCodeXtra 0.2.5.5
BugMeNot 1.3
Colorful Tabs 1.4
ColorZilla 0.8.3.1
CustomizeGoogle 0.52
CuteMenus 2 1.0
DictionarySearch 1.5
Disable Targets For Downloads 1.0.1
Download Embedded 0.4
Download Statusbar 0.9.4.1
DownloadHelper 1.91
DownThemAll! 0.9.9.6.5
ErrorZilla 0.2
Fasterfox 1.0.3
Favicon Picker 2 0.3.3
Forecastfox 0.9.3.1
FxIF 0.2.2
IE View 1.3.1
Image Zoom 0.2.7
ListZilla 0.8
Methusalem 0.3
Multi Bookmarks Toolbars 0.9.2
Noia 2.0 (eXtreme) 3.01
Nuke Anything Enhanced 0.53
PDF Download 0.7.6
Screen grab! 0.6
ShowIP 0.8.05
Sort Extensions and Themes 3.0.2
Sourceforge Direct Download 0.5
Tab Mix Plus 0.3.0.5
Translate 0.6.0.8
Web Developer
Input is welcomed.

Link: Firefox Flicks: Wheee!
Link: More
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As an experiment, this person installed 100 of the most popular of the 1148 extensions available from Mozilla Update.
Remarkably, the browser was still stable.

Link: Screenshot
Link: Story
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So, since greasemonkey doesn't work w/1.5, some favorites are gone, yes? Well, these aren't much, but they give you the prev & next buttons on StrongBad emails, and the other gives the fullscreen option! That's good enough 4 me!!
Link: StrongBad Emails: Prev & Next
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Full Screen Homestarrunner

Interesting..  I'm using this extension now to make this post. Read more..

Internet Explorer users are at least four times as likely to click on Web ads than Firefox users, a German advertising technology company said last week.

Hmm, maybe I should quit promoting Firefox so much; I kinda want people to click some ads...
Although:

Firefox users may be more likely to click on targeted ads, rather than other types. "Most people I know are more happy with Google's targeted ads--they don't like big banner ads that are totally unrelated to what they're looking for," Hallowell said.

So that works too.
Link: Firefox users ignore online ads, report says | CNET News.com
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After making the switch to Firefox 1.5, here are the add-ons I currently have installed. (list generated by this extension, great for keeping a back-up record)

Please comment if you have any suggestions..

Enabled Extensions: (28)

All-in-One Gestures 0.17.4
Alt-Text for Links 0.3
BBCodeXtra 0.2.5.4
BugMeNot 0.8
Colorful Tabs 0.3
ColorZilla 0.8.3.1
CustomizeGoogle 0.39
CuteMenus 2 0.6.2
DictionarySearch 1.5
Disable Targets For Downloads 1.0
Download Embedded 0.1
Download Statusbar 0.9.4
Fasterfox 0.7.9
Forecastfox 0.8.2.5
IE View 1.2.7
Image Zoom 0.2.1
ListZilla 0.7
Methusalem 0.3
Noia 2.0 (eXtreme) 2.991
PDF Download 0.5.1.2
Popup ALT Attribute 1.3.2005092701
Screen grab! 0.6
Tab Preview 0.3
Tabbrowser Preferences 1.2.8.7
Translate 0.6.0.8
Viamatic foXpose 0.2
Web Developer 0.9.4
zoomFox 0.72

Here's a cool new extension for firefox 1.5
Link: Mozilla Update :: Extensions -- More Info:Viamatic foXpose - All Releases
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An extension for the cynic in all of us!
Link: US Department of Homeland Insecurity Idiocy Level
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It's been a long day waiting for this.. I'd tried a couple of beta versions, but the wait is finally over; here's the real deal.
Also, check out the brand new mozilla.com (formerly just a splash screen directing visitors to mozilla.org, which is now a splash screen directing visitors back..)
*note: I have read that this will knock out greasemonkey and some extensions, but whatever, I'm sure they'll be updating soon enough to comply with the new standard..
Link: Firefox - Rediscover the web

Link: Kill Bill's Browser - Switch to Firefox
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I've used the unembed script for greasemonkey for a while now, but sometimes the download button doesn't show up.. Here's an extension which allows you to right-click on the page and do the same.
Link: Download Embedded
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Google now pays $1 for each Firefox download with the Google Toolbar installed.

neat.
Link: Google Paying for Firefox Installs

Also, the customizable RSS feed.
Link: Pornzilla: Free tools for surfing porn with Firefox
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neat.
Link: Mozilla Update :: Extensions -- More Info:Colorful Tabs - All Releases
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Link: 100,000,000 DOWNLOADS! | Spread Firefox
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