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