IBM's RFID tag features range clipping security
Specifically, the tag contains a disabling feature that limits the chip's ability to broadcast its signature. This disabling feature is called a Clipped Tag and has perforations. You can tear the tag along those perforations and sever the antenna. This action does not stop all transmissions; rather, the transmission range is just a few inches rather than the tens of feet that are possible with a fully equipped chip. Despite this severing, the antenna retains its ability to transmit its data.
The demonstration is expected to take place sometime this week at the RFID Journal Live conference in Las Vegas.