How about an active and passive RFID combo? Very soon Seiko Precision will be coming up with hybrid RFID tags where you will get active and passive RFID tags on a single package. Dubbed as SecureTag WT-300 it would be offering dual communication ranges.

With active tag you will be getting a range of 50cm whereas the passive tag offers a shorter communication range. The former could be used for tracking whereabouts of people whereas the latter can be put to use for authentication purposes. Have a look at their press release.

Via ubiks