Poweradmin is a web-based DNS administration tool for PowerDNS server. The interface has full support for most of the features of PowerDNS. It has full support for all zone types, for supermasters, full support for IPv6 and multi-language support.
izidns is a web-mysql-based front-end (based on PowerAdmin) for the bind (http://www.isc.org/sw/bind/) DNS server.
Not like the commercial interface 'eazyDNS', izidns fully supports PTR record usage (rDNS) and is released under the GPL :-)
Rubberduck is a simple TODO Manager using MySQL and PHP. The priority of TODO items can be easily read by using a simple colour set. This TODO manager was released for use within the PowerAdmin project but was made Open Source after various requests.