Here is a list over my favorite community tools:
ConfigMgr Prerequisites Tool
Description: ConfigMgr Prerequisites Tool is design to help administrators prepare their infrastructure and systems when about to install Configuration Manager.
Author: Nickolaj Andersen
Download: https://gallery.technet.microsoft.com/ConfigMgr-2012-R2-e52919cd
LogLauncher
Description: A simple tool that brings ConfigMgr related and other logs together in one simple view.
Author: Robert Marshall
Download: https://gallery.technet.microsoft.com/LogLauncher-61ba5c99