IRLP
www.irlp.net
The Internet Radio Linking Project, allowing Amateur Radio repeaters and links to communicate with one another via the Internet, using voice-over-IP (VoIP) technology.

EchoLink
www.echolink.org
EchoLink® software that allows Amateur Radio stations to communicate with one another over the Internet, using voice-over-IP (VoIP) technology.

EchoLink Map Project
www.echolinkmap.org
A site founded by N4WWC that displays EchoLink® nodes around the world using maps.

New England Repeater Directory
www.nerepeaters.com
The most accurate repeater directory on the Internet for repeaters in the six New England states on 29MHz and above.

New York Repeater Directory
www.nyrepeaters.com
A sister site of the New England Repeater Directory above.  This site currently lists repeaters on 29MHz and above in Eastern NY State and Long Island NY.

QRZ
www.qrz.com
A site founded by Fred Lloyd, AA7BQ designed to lookup any Amateur Radio operator's information, with additional interesting features.

Ventrilo
www.ventrilo.com
Ventrilo is evolutionary step of Voice over IP (VoIP) group communications software, best known for it's superior sound quality and minimal use of CPU resources.