I do almost everything online. Since my family is farflung and my friends scattered across the globe, the fastest, least expensive, and most reliable way to stay connected with them is via internet. We have back-up in case the internet fails us, or if one of us is in an internet-less area (my children in the military are often in zones lacking internet)
For the most part, though, I rely on the internet for communication.
Here's how I keep connected:
1) I have a facebook account opened with a gmail account created specifically for that facebook. It doesn't tie back to me directly, and I did this because of facebook's erratic privacy policies. I keep up with my family there, and with distant friends. I also use the group function for volunteer work and planning events. A lot of people dislike facebook, but I think it's because they have this mistaken idea that you have to accept every "friend" request and play all the games and get involved in all the questionnaires and such, and they don't adjust their privacy settings. I don't play games, do the surveys, pass along the rumors, and such.
2) Email - I have several emails for different purposes - easier than sorting them into folders when the email services keep changing their features on you and messing up your sorts. Mostly, I use gmail, but I also use Yahoo mail. I don't use hotmail because I had some seriously bad experiences with them and will not go back. I don't use email through my ISP, mostly because they randomly reset the passwords and I got tired of having to go in person to deal with this - being hearing impaired can suck at times.
3) I have Skype for international calls, since it's video, I can manage to figure out what the other person is saying and Skype offers a speech to text program and an accompanying chat room so I don't miss anything.
4) I now have a cell phone with texting capabilities. I am not comfortable with it yet, and it has a hideous touch screen that refuses to recognize my touch, so I am going to get a stylus and see if that helps. I hate the cell phone. But I am going to learn to use it anyway.
5) I've discovered that, depending upon which country I am trying to contact, local cell providers may have websites through which you can send text messages or web messages. It's kind of hit or miss, but it works in war zones better than Skype or email.
6) I blog. A lot. On multiple platforms. And comment. I like LJ and DailyKos best because they are more interactive, but I also use Blogger and WordPress and a few others.
7) I just got a twitter account and am learning how to use it. That may become an important part of communicating once I figure it all out and become comfortable with it.
8) Although I don't travel, my kids in the military do, and they carry an "unlocked" cell phone. When they arrive at their destination, they buy a SIM card and a "load" from the local cellular provider and then they have cell service which is much cheaper than using the state-side cell service overseas.
9) Letters, cards, and postcards. I make my own postcards with pictures I take - they mean a lot more to my kids than generic store-bought postcards. Snail mail is always a decent back up for communications.
10) Personal couriers. I like using friends and family who are traveling to carry packages and such either to their destination or to pass along to someone who is going the right way so the package eventually ends up at its destination. I find this is more reliable than the Post Office and sometimes it's even quicker.
11) HAM radio. If you don't have one, why not? You can communicate surprisingly quickly with one. I have mine attached to a computer that has a speech to text program. It garbles a lot, but I can usually puzzle out what's being said. And others don't seem to mind repeating so the program catches it.
12) CB radio - I fell in love with the CB back in the 70's and still use it as a back up way to communicate, but now I have to use someone as an interpreter because I can't hear it anymore. I like it better than cell phones when driving and since I usually have a passenger, they can handle the CB radio traffic.
13) In person. Never underestimate the value of seeing people in person, visiting them in their homes, inviting them to yours. Getting to know your neighbors is important, too, because they are the closest people when a disaster happens, and it's good to know who they are. Also, if you have elderly neighbors like my 104 year old one, checking up on them is crucial to make sure they are doing well. Also, walking, biking, or driving to the location where you need to communicate. I do this a lot since I'm hearing impaired, it's much easier to deal with them in person than to try to deal with them via voice recordings I can't hear well and that garble on the speech to text program a lot - a lot of places don't like it when you show up in person to deal with an issue, but if you're persistent and play dumb, you eventually get what you need.
14) Two-Way FRS/GMRS radio. These walkie-talkies are useful in limited situations. I like making sure our party has one when we attend fairs and festivals, indoor or outdoors. and when we go camping, so we can stay in touch and find one another, or alert one another to special finds. I usually have to find someone to listen to it for me when Itzl alerts on it, but so far, everyone I've asked to listen for me has been happy to do so.
How do you stay in touch with people and what back up communications do you have in place in case one or another stops working, however briefly?