802.15 beyond bluetooth of interest re licence-exempt wireless, and the development of "personal area networks" or "wireless personal area networks" (PAN and WPAN). I think it was Nokia who recently envisaged a PAN device in the form of a wrist-watch...
Bluetooth IEEE consortium have now evolved into 802.15 (.3 .4 and .5) for low-, high- data and mesh wireless routing (saves battery etc).
See this useful
overview:
scroll to IEEE 802.15 WPAN Standard
And further re google results for
IEEE etc.: