Idea: datatransmission using ultrasound

[Ole Tange]

Apparently the Neo may be capable of transmitting ultrasound (20 KHz -
around 45 KHz). If the Neo is also capable of receiving this (using
the microphone) then we should be able to transmit data that way. This
may be useful for close range network (e.g. transmit business card).

The protocol will be similar to wireless ethernet. The range will be
similar to Bluetooth.

/Ole