DISCLAIMER: The following are purely based on my opinion-- not influenced by someone else's.
- On facebook: TAGGING YOURSELF IN YOUR OWN PHOTO/PHOTO ALBUM POSTED IN YOUR PROFILE/TIMELINE. Do you really have to? I believe that the tagging feature of FB is for the pic to be posted in your friend's timeline as well, most especially if you are the only one bringing a cam or taking the pic. Or it could be also to show to the whole cyberworld who you were with. But that tagging yourself in the pic that you posted, it doesn't really make sense. The pic will appear in your profile/timeline anyway even without you tagging.
- On facebook still: LIKING YOUR OWN STATUS OR PIC. Now this is way too annoying for me. I couldn't get it why some people do this. When you post a status or a pic, it means that you feel strongly for said status or pic or at least wanted such to be seen on your timeline, otherwise you wouldn't post it. Liking your own status or pic spells nothing but redundancy. Or it could be that you're afraid no one will like your post, so you do it yourself. At least you have 1 like. Pathetic, isn't it?
- On Foursquare: CHECKING-IN ON A STREET! My goodness! The last time I checked, a street in not a restaurant, hotel, mall, or an establishment for that matter. Yes, it is a place but this constitutes abuse of the essence of Foursquare already. You are just inviting stalkers or worst, hired killers to track your whereabouts. You are turning foursquare as a GPS device.
- On Twitter: EXCESSIVE RE-TWEETING AND HASHTAGS. Twitter proved to be the fastest way to get the word around. I turn to twitter to get the latest news on important current events. Sadly, there are those who don't tweet responsibly and flood your timeline with sometimes nonsense re-tweets. I also couldn't take those who tweet with overly many hashtags. We are given a limited number of characters for our tweet and consuming the little that we have with numerous hashtags defeats the purpose of twitter for me.
I can enumerate some more like washing your dirty linens on FB, cursing or harassing someone you don't like on twitter, telling everyone what you are doing every single second, but these I can tolerate to a certain extent. The ones I mentioned above have gone beyond my maximum tolerance.
Oh well, I'm just glad that facebook has the 'hide' feature.