I am spending a good portion of my waking hours at the KDS Reading Center this summer. Class starts with introducing iPads. My students last year have never used an iPad. This year I have about 20% that have personal iPads. Now we provide everyone with an iPad for use during tutoring while some educational systems are buying devices in bulk, teachers are buying individual devices and changing their own classroom circumstance from the bottom up.
At first the potential expenditure considering teacher salaries took me a back a bit. But then I reflected that teachers have always supplemented what districts and schools provide with things they bought on their own. This is just a single larger purchase, on the other hand unlike a glue stick it is not just for the classroom.
A single teacher owned device in the classroom is not a solution for technology integration, but it is a start. If supported with some casual professional development it can become the foundation to wider, successful mobile adoption when student devices become reality. As with other technologies, small scale use will produce local expertise that can be leveraged when wider implementation of mobile happens at the school.
Of course schools can help along by purchasing a few devices for teachers...