Rsyslog, the enhanced syslogd for Linux and Unix.
Rsyslog is an enhanced multi-threaded syslogd supporting, among others, MySQL, syslog/tcp, RFC 3195, permitted sender lists, filtering on any message part, and fine grain output format control.
It is quite compatible to stock sysklogd and can be used as a drop-in replacement.
Its advanced features make it suitable for enterprise-class, encryption protected syslog relay chains while at the same time being very easy to setup for the novice user. An optional web interface - phpLogCon - can be used to visualize all data online.