Chef
Configuration management tool which uses a pure-Ruby, domain-specific language (DSL) for writing system configuration recipes. Supports Linux, UNIX, Windows, and AIX as first-class citizens for management.
linux windows open-source comercial provisioning config-mgmt ruby
Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
linux osx open-source monitoring process-mgmt c
Puppet
Puppet is a tool designed to manage the configuration of Unix-like and Microsoft Windows systems declaratively.
linux windows osx open-source config-mgmt ruby