ispacct is an accounting package for Internet Service Providers. At the moment it has accounting infrastructure for Bintec routers and sendmail logfiles. It can output as plaintext, HTML or into a MySQL DB:
Linx URL filter is a console filter used to retrieve and filter the text contents of web pages. Linx URL filter uses plugins to extract information like tags, links, mail addresses and scripts
LogD (Log Daemon) is an Open Source Meta Mod (www.metamod.org) plugin for Half-Life Servers. It decodes log messages through the use of the Half-Life API to notify other plugins of events otherwise undetectable.