GlimmerBlocker is no longer maintained and should no longer be used as web sites have migrated from using plain http to using https (i.e. encrypted) which prohibits modification by a proxy unless you resort to install custom SSL certiticates on the client.
You should use a browser extension instead.
It was made as a hobby project during 2007-2008 by Peter Speck. It features both a custom http server and http client and a Mac OS X control panel.
Download: GlimmerBlocker-1.6.6.dmg (release notes).
This version requires macOS 10.10 (Yosemite), 10.11 (El Capitan) or 10.12 (Sierra). After upgrading macOS, you might have to reinstall GlimmerBlocker. Older versions of GlimmerBlocker supports older versions of OSX. There is no version for iPhone.
Easy to uninstall if you don't like it anyway.
GlimmerBlocker is free: No payments required, but please help spread the word as ad-based sites would very much like to keep it a secret.
Screenshots gallery and detailed installation help.
The problem with other ad-blockers for Safari is that they are implemented as awful hacks: as an InputManager and/or ApplicationEnhancer. This compromises the stability of Safari and very often create problems when Apple releases a new version of Safari. Snow Leopard doesn't support the InputManager-based blockers when Safari runs in 64-bit mode.
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. The proxy runs on the mac and not on a central server like most proxies.
You'll always be able to upgrade Safari without breaking GlimmerBlocker (or waiting for a new release); and you'll be able to upgrade GlimmerBlocker without upgrading Safari. This makes it much easier to use the beta versions of Safari and especially the nightly builds of WebKit.
Guido's description of GlimmerBlocker in German, and Fingster Kevin's description and filter for Chinese users.
A set of default filters for common worldwide ad-providers are included in GlimmerBlocker. So out-of-the box it blocks most ads. If you still see ads on common, high-traffic sites, please notify me so the filters can be improved.
You can create your own filters and publish them using MobileMe or plain WebDav so other users can subscribe to your filter.
See the list of filters which other users have published.
You can setup iPhone/iPod to use GlimmerBlocker when they're using wifi.
The following applications needs workarounds or configured:
Very short FAQ.
GlimmerBlocker is fully open source and is licensed using GPLv3. You can download the source, make your own modifications, submit changes, etc.
Older versions can be found in the downloads directory. Sparkle uses two rss feeds: official releases and beta releases. Even though the rss feeds includes a link to the new version, the easiest method to update GlimmerBlocker is to open the "System Preferences", choose GlimmerBlocker and click "check now" in the "Setup" tab pane.
Send feedback and bug-reports to firstname.lastname@example.org