Michael Karlesky recently gave a talk at Cornell as part of their d:Tech series called Playing Around: Taken Seriously. 

Humans have been playing with technology for all of recorded history (think way bigger than video games). In fact, one name for our species is Homo Ludens—Man the Player. More often than not the word “play” connotes triviality. But play is anything but trivial and more than games. As technology has grown more powerful, technology design goals have evolved to encompass values more than only utility or even productivity. Ph.D. candidate Michael Karlesky will present his ongoing work on a theory for playful technology arguing for its value and benefit in technology design, concluding with early thoughts on how to design for playfulness.

He's also started a blog series expanding upon the topic coved in that presentation.  You can read it here!