Don Park

http://www.rfidsupplychain.com/-strse-216/Alien-Squiggle-SQ-RFID/Detail.bok
$350 for 500 units. (70 cents each) ISO/IEC 18000-6C EPC Class 1 Gen 2 860-960 MHz

http://mouser.com/Search/ProductDetail.aspx?qs=sGAEpiMZZMuXfccvO5DzatroL884im7I
$225 for 500 (45 cents each). ISO 15693, ISO 18000-3 13.56MHz

http://www.sparkfun.com/commerce/product_info.php?products_id=8310
$2 RFID Tag 125kHz EM4001

http://www.sparkfun.com/commerce/product_info.php?products_id=8709
RFID Reader-2 $25 125kHz, EM4001 (EM4100 compatible, i think)
http://www.sparkfun.com/commerce/product_info.php?products_id=8423
RFID Reader breakout $1

Arduino+XBEE
http://www.sparkfun.com/commerce/product_info.php?products_id=666
Arduino USB Board $30
http://www.sparkfun.com/commerce/product_info.php?products_id=8691
XBEE 2mW $25
http://www.sparkfun.com/commerce/product_info.php?products_id=9063
XBee Shield $25

Battery
8 AA (12v), AA Holders, DC plug

http://mouser.com/Search/ProductDetail.aspx?qs=Ok6sVjDQtqZe%252bxNkVrl%252bWg%3d%3d
Parallax RFID reader $40, EM4100 1-3" range

https://shop.openpcd.de/product_info.php?products_id=42&osCsid=g8e3t1fgs3iqmd49o3t0fmobj4
OpenBeacon USB node $115

http://tinkerit.myshopify.com/products/rfid-kit
RFID Shield Kit, 13.56MHz Mifare module 10cm range $56

Rfduino
http://rfid.marcboon.com/#home
http://trac.mediamatic.nl/picnic/wiki/RfiDuino

Mifare module, with USB interface
http://www.sonmicro.com/en/onlinestore/index.php?page=shop.product_details&flypage=myflypage.tpl&product_id=33&category_id=19&option=com_virtuemart&Itemid=43&vmcchk=1&Itemid=43

Mifare module, with usb interface
http://www.rfidgeek.com/index.php?n=RFID.USBRFIDReader
http://www.cncgeeker.com/index.php?main_page=product_info&products_id=29&zenid=07f68c6b3cc3a6d2224d6e614ccb3b0e

http://trac.mediamatic.nl/picnic/wiki/RfiDuino

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1223861029 http://www.schneier.com/blog/archives/2006/11/skimming_rfid_c.html http://www.rpi-polymath.com/ducttape/RFIDWallet.php http://blog.wired.com/gadgets/2008/02/rfid-reader-to.html