Safari doesn't handle ad blockers very well and those that do exist often work very erratically or too efficiently, blocking everything in sight.
The designers of GlimmerBlocker claim that it's a much more efficient and safer ad blocker for Safari because it is implemented as an http proxy. This means that the stability of Safari isn't compromised because it doesn't use any hacks and consequently, it also works with other browsers. The other big advantage of GlimmerBlocker is that it won't break either when you upgrade Safari.
GlimmerBlocker allows you to block images by right clicking on them and also allows you to specify which cookies are allowed from 3rd party sites. GlimmerBlocker even allows you to add modifications to pages by adding CSS rules and Javascript or by transforming the HTML before Safari receives it. In this respect, it's also an ad blocker for more advanced users, which is considerably more effective than most but does require some CSS and Javascript knowledge to get the most out of it.
GlimmerBlocker is an excellent ad blocking tool that's ideal for Safari users with some knowledge of how CSS and Javascript work.
