AdSubtract allows you to harness Safari's built-in capacity to use Custom Style Sheets as an ad-blocking solution.
When you download things in Safari, DownloadComment will put the original URL into the saved file's Finder Comments.
DownThemAll! (or just dTa) is a powerful yet easy-to-use Mozilla Firefox extension that adds new advanced download capabilities to your browser. Read more
Forget Me Not
Forget Me Not is a Safari plug-in which remembers the tabs and windows you have opened when you quit Safari, and reloads those same windows and tabs when you restart Safari.
GlimmerBlocker is implemented as an http proxy, so the stability of Safari isn't compromised because it doesn't use any hacks. It is even compatible with all other browsers and other native Mac OS X applications which uses http, e.g. NetNewsWire.
Keywurl adds functionality to Safari similar to the search functionality in Firefox and Opera. Type a keyword and a query in the address bar, and it will be expanded into a predefined search.
Lestrade is a handy tool designed to give you quick and convenient access to many popular search engines. Lestrade provides a small unobtrusive floating window. Enter a search query, select an engine and your search results appear in your internet browser.
Pangea VR is a web browser plug-in for Mac OS X that allows you to view VR panoramas with unprecendented quality and speed.
Portable Safari.app is a shell script that open local copy of Safari? using preferences stored in its application bundle. ~/Library/Application Support/Safari and ~/Library/Caches/Safari folders and ~/Library/Preferences/com.apple.Safari.plist file are temporary renamed with .pabu extension and a symlink is created to use portable ones.
With this little tool it is possible to open and display Konqueror web archive format. This format is used by the Konqueror web browser and file manager to save complete web sites including images. This is similar to Apple's web archive format used by Safari.
Surf Canyon for Firefox
Surf Canyon accelerates the search experience on Google, Yahoo!, and Microsoft Live Search by enabling you to find relevant information buried in the search results.
SurfRabbit is a browser add-on for the Safari and Shiira web browsers that will allow you to customize how pages from almost any site is displayed.
User Agent is a prefpane for Camino.
Webarcher is a small utility designed to convert the well known Safari webarchive format to the Konqueror war archives or to download HTML pages as war archives.