Google Plus

I use PA software to get rid of as much trackers, bload, and other crap as possible. Putting an +1 button, or facebook like for that matter, only puts a tracker of those businesses on this website that can monitor us and create more complete profiles.
I share the awesome PA suite with friends by telling them about it, not by liking it on any social media.

It's clear that I am a massive privacy freak. The whole concept of determining for the user what content is relevant or not, like google and facebook are doing on an unprecedented scale, is something that can really get me riled up. If there is an option to like or +1 externally without them having that tracker shit on here then, by all means, go ahead.