VoIP - SIP and RTP stacks, softphones, user agents, STUN

ENUM Softphone: An Open Source Softphone for Windows based on Microsoft's RTC API; uses the ENUM SDK from JPRS. Homepage: http://www.enum.at/index.php?id=softphone
Generic Gateway: An ENUM driven PSTN to VoIP Gateway with support for SIP, H.323 and Ifax, based on a Cisco GW. Homepage: http://www.enum.at/index.php?id=380
Perl ENUM Module: An Open Source ENUM module for Perl written by JPRS. Homepage: http://jprs.co.jp/enum/software/software.html
ENUM Active-X Control: An Open Source Active-X Control for Windows written by JRPS. Homepage: http://jprs.co.jp/enum/software/software.html
IETF: The IETF ENUM Working Group; Homepage: http://www.ietf.org/html.charters/enum-charter.html

RIPE: The tier-0 authority for ENUM; Homepage: http://www.ripe.net/enum/
enum.at: The tier-1 authority for ENUM in Austria. Lots of ENUM related information; Homepage: http://enum.at/