Venkat at RibbonFarm talks about ambient presence a concept that was new to me:
Let’s say you and your spouse work in different cities. You both sign up for a VoIP service like Skype, but instead of dutifully talking every evening, you just turn up the speakers on your respective computers, and leave the Skype connection on. You occasionally say something to each other; you can hear each other’s TVs and kitchen noises. That’s ambient presence. Communication technology becoming so cheap that you can afford to leave it on to create a passive background connection. It is a pretty darn cool concept, so let’s take a serious look at it.
See full article.
This seems to me like a rather powerful idea. Some people are already using this in the IM/chat context. Keeping an IM window open and randomly throwing out a few lines every once in a while is something people have started doing more and more. But if we could extend this to other media (like phones) that could change how we communicate with certain people.