Like not implementing cookies, LocalStorage, screen resolution info, font enumeration, canvas, WebGL, WebRTC, etc etc?
It's probably realistically possible to disable those with the existing browsers. Problem is, that will also break sites that expect you to have all those available. And it's said that there are too many of those (I never saw a proper analysis, though)
Just consider: there are sites (one of my favorite pizza delivery sites does that) that break if you just block Google Analytics ga.js (or their newer versions, whatever they're called) scripts. Just because they have stuff like `_gaq.push` hardcoded into click handlers and if those raise exceptions, they fail.