We present an initial exploration of bluejacking, the practice of using Bluetooth-enabled mobile phones to send unsolicited messages to other Bluetooth-enabled mobile phones within a transmission range of 10 meters. A content analysis was conducted on 427 bluejacks from Bluejackq, an online community of bluejackers, in which the contextual characteristics of bluejacking were examined. Bluejacking was found to be highly location-dependent, primarily transpiring in everyday public places. The message content of the bluejacks was also inspired by the physical location where bluejacking took place. We also discuss implications of bluejacking with regards to its relationship to public space and comment on how these findings are relevant to mobile social computing. Keywords Bluejacking, mobile phones, Bluetooth, public space, territoriality ACM Classification Keywords H5.3 [Information Interfaces and Presentation]: Group and Organizational Interfaces