I usually use a few different tried and true methods of communication. My primary means of communication is texting via cell phone (I'm not much for that whole SMS-to-email/IM thing). That probably sounds shallow, but I'm not your regular "hehe hw r u? im bord i at BK wat u doing?" kind of person. Heh. No. I don't abbreviate anything, save the typical IM/text words LOL, OMG, WTH...you get the idea. For me as a writer, texting is a glorious and enjoyable way of communicating. I talk about meaningful things, and I am easily able to carry on a convo with most people as a result of rapidly tapping on my QWERTY keypad. Without looking. WIN.
My second most-used line of communication is Facebook. If quite a few of my friends don't have cell phones (poor souls) or texting (gasp), I can almost always talk to them on FB chat (which DOES suck for the most part), message them, or write on their walls. My third and less frequent but still most effective means of communication IMO is that of phone calls. Whether they be landline, cell, or Skype calls, actually hearing the other person's voice on the other end breaks down alot of communication barriers for alot of people I know. I've found that this method of keeping in touch is also more efficient (less frequent miscommunications, more detectable tones) and allows the conversation to get more personal than it would by using another communication option. I use a few other ways to communicate with my friends, but those are significantly lower on the ladder than those I have listed above. Regardless of what method I use at any given time, I owe a huge thanks to technology - it makes keeping in touch so much faster and easier! 
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