As expected, Google used its I/O conference to shed some more light on its Project Glass prototypes. And in doing so, it pulled out all the stops, equipping skydivers with the glasses and streaming their perspectives as they swooped down at 135 mph, eventually onto the roof of the Moscone Center, where the conference was ongoing. After the divers arrived, Google co-founder Sergey Brin announced the device’s price tag: $1,500 a pair, available beginning next year to developers only—presumably to afford them the opportunity to create consumer apps before the devices have a full, commercial release.