What I want from Christmas: RFID scanner

Aside from my “amazon wish list”:http://www.amazon.com/gp/registry/registry.html/002-9667547-1938447?%5Fencoding=UTF8&id=3JYVDAXJZBNPD , I want an RFID scanner, that I can install around my front door (so it must blend in). I want to know what RFID tags there are out there, and where they are coming from. Google doesn’t show up anything like a RFID scanner that can be put in a doorway.

While poking around ebay for RFID I got this: VeriChip TXI400L Implantable Security Microchip with Injector Kit. I guess you could give me one of these and we could inject the cats!