At this point, there is a pretty good chance that if you live in the US, you either have a smartphone or know someone who does, so you are familiar with touchscreens on mobile devices. This now ubiquitous interface system has changed the way many people interact with technology today, but there are still some areas it has not affected. For example, despite touch technology being common for smartphones, when actually making a phone call, it is not used, but researchers at University of Helsinki are changing that.
The researchers have created prototype phones called ForcePhones that allow 'pressages' to be sent. These are non-verbal messages that convey the pressure of one person touching their phone to the other person. The researchers gave the ForcePhones to people, to learn how they use them and found that with an average phone call lasting 4 minutes and 43 seconds, there was an average 15.56 pressages sent, and all calls involved pressages. The subjects admitted to using the pressages to emphasis a point, express emotion, or to simply surprise whoever they were talking to.
The ForcePhones are not especially unique phones as they actually are standard mobile phones that have been augmented with pressure sensors for input and vibrotactile devices for output. However, I wouldn't be surprised if it still takes a while before we see this in the next line of smartphones.