[abrowne]

Another option for Firefox is the built-in "tracking protection". It is off by default, but can be enabled via about:config (set privacy.trackingprotection.enabled to true). Works on Android, too.

[HunOL]

And it breaks a lot of web sites.

[acdha]

Have you reported those? I've only encountered one and it was apparently fixed awhile back.

[abrowne]

I've haven't noticed any problems myself. I run mostly Firefox Beta on OS X, Linux, and Android and have been using it since late May.

[rockdoe]

Yes, the ones that track you. That's the point, isn't it.