Fluentd: Unified Logging Layer (project under CNCF)
Apache Log Parser and Data Normalization Application
Ansible role which installs and configures Graylog
DTail is a distributed DevOps tool for tailing, grepping, catting logs
A powerful terminal app for structured log streaming
A nginx log explorer
Elasticsearch/Splunk/Datadog alternative for (logs, metrics, traces)
Qualitis is a one-stop data quality management platform
Logging Framework for C++
C++ library for easy and flexible logging
A replica of the logrotate utility, except this also runs on Windows
A fake log generator for common log formats
Extensible log shipper with input/output plugins, buffering, etc.
Easy, flexible, lightweight, platform independent C++logging library
LogDNA Agent streams from log files to your LogDNA account
Sematext Logs Client Library for Android
Open Source SIEM
Radio logging for Search and Rescue
Log Management Web Application
YXDroid