Microsoft have been getting lots of press recently because of their new Zune music player. One of its major features is its wireless interface that lets you share music; even most of the advertising talks about the social implications1. But let’s have a quick look at that functionality in more detail.
If I decide that I want to expend an hour of battery life in order to see other Zunes in the area, what can I do? Most famously you can transfer songs. As I’m sure you’ve heard by now, there are limits. When I receive a song, I can play it three times or hang onto it for three days2 but after that all I get is an electronic post-it note reminding me about it. Clearly a lot of thought and a lot of engineering effort has gone into these limitations.