Lire is a pluggable log analyzer. It has analyzers for over 25 log file formats, ranging from Apache WWW log files to iptables firewall logs and CUPS printing logs. Reports are generated in 9 different output formats, ranging from Excel 95 to PDF to HTML, optionally with included graphs.
ICPLD (Internet Connection Performance Logging Daemon) is a connection monitor that sends ICMP requests to IP addresses of your choice and monitors if your machine has a working network connection. It logs failed attempts to reach the hosts, and will stamp a log as soon as a reply is received. It keeps track of when and for how long the connection was unavailable and records both total down time and each occasion of interrupted connection. It supports IPv6 and can execute a command whenever a connection goes up or down, which is useful for alerting users.
Logger is a log queueing and optimization utility. It can completely replace sys/klogd, handle logs larger than 2GB, perform automatic nightly log rotation without affecting services, and transfer logs between machines via TCP connections. Any application that writes a text log can be maintained by Logger. It is light, small, and fast, emphasizes security, and reduces drive usage through memory queueing.