The invention relates to an event driven content switching technology in a passive, batteryless radio frequency identification (RFID) tag. The RFID tag device monitors the occurence of an external event such as a change in the environment. The switching of the context of the tag is effected by sensors incorporated in the tag. An external event triggers the switch. An RFID reader may subsequently read out the occurrence of the event due to the switch change. Different alignments of the switch could bring about the closing or opening of specific electronic circuits within the RFID tag that effect the storing of information in a selected memory, or changing the ID transmitted by the tag. In a particular embodiment this latter is accomplished by shorting one or the other of two RFID tag antennas. When one antenna is shorted, the second tag's ID is sent, and vice versa.