Issuetrak - Issue tracking software for help desk and customer service
logstash - logstash is a tool for managing events and logs.
Deskun - Deskun is a Help Desk system inside Gmail. It enables you to support customers directly from your mailbox, manage projects, and use free features for Gmail.
rsyslog - Rsyslog is an enhanced syslogd supporting, among others, MySQL, PostgreSQL, failover log...
Kapdesk - Kapdesk offers support teams with a helpdesk software to streamline support tasks.
Graylog - Graylog is an open source log management platform for collecting, indexing, and analyzing both structured and unstructured data.