I remember seeing a really interesting site a while back that challenged the convention of clicking: http://www.dontclick.it/ (it's a safe site, it uses mouse movement instead of clicking for interaction. The don't click does not refer to not clicking the url) :)
What this site points out is fascinating. It proves just how accustomed we are to clicking on things when we interact with an interface. Although it required a lot of cognitive effort to go against the convention of clicking, it seemed as though it was opening new doors in terms of unique interactive experiences. At first several uses, it is difficult and not very usable, but with retraining or first use training (kids using computer for the first time) it could work.
With the rise of touchscreen mobile devices (phones, tablets, etc) are we now locked into the concept of tapping/clicking? It seems like ideas like this would never work if the future of computing moved more into the direct of touch interfaces. Sure we have gestures, which are similar in terms of breaking the click habit, but even those have some element of clicking, or at least applying pressure to the screen.
Is the idea of having a unique interface such as the one seen on dontclick.it at the end of a dead end street, or is it possible to use something like this with a kiosk type installation at a museum or something similar?(with the use of a mouse, not touch)
*Please note that I am not at all advocating we get rid of clicking or that a click-less interface is easy to use, I just think that the idea that this concept is such a challenge to users tells us a lot about the importance of user expectations (why they exist and how/when to challenge them).