Faleron's Stars
ConSol/sakuli
Sakuli is an end-2-end testing and monitoring tool for web sites and common UIs with multiple monitoring integrations
lausser/check_oracle_health
A plugin (monitoring-plugin, not nagios-plugin, see also http://is.gd/PP1330) which checks various parameters of Oracle database servers. (We also offer trainings: http://www.consol.de/open-source-monitoring/schulungen/workshops/#datenbank-monitoring)