SharePoint 2010 Designer – SharePoint Designer 2010 is the tool of choice for the rapid development of SharePoint applications from Microsoft and is free to download.
SharePoint 2013 Designer – SharePoint Designer 2013 is the tool of choice for the rapid development of SharePoint applications from Microsoft and is free to download.
SharePoint Administration Toolkit – The Microsoft® SharePoint® 2010 Administration Toolkit contains functionality to help administer and manage Microsoft® SharePoint® Foundation 2010 and Microsoft® SharePoint® Server 2010
SharePoint 2010 and Office Server 2010 SP1 packages – This article lists all the Microsoft SharePoint 2010 and Office Server 2010 Service Pack 1 (SP1) packages and the information about how to obtain them
Language packs for SharePoint 2010 – Language packs enable creation of sites and site collections in multiple languages without requiring separate installations of SharePoint Server
SharePoint Manager – A SharePoint object model explorer that enables you to browse every site on the local farm and view every property.
AutoSPInstaller – A set of PowerShell scripts and an XML input file which that provide a quick and near-unattended installation and initial configuration (Service Apps, My Sites) of Microsoft SharePoint Server 2010/2013
AutoSPInstaller Source Builder – A free utility for building a SharePoint 2010 & 2013 install source including prerequisites, service packs, language packs & cumulative updates.
AutoSPInstaller GUI – A very nice GUI for editing your AutoSPInstallerInput.XML file
ManageEngine SharePoint Health Analyzer – A free tool that monitors SharePoint 2007 and 2010 servers
SUSHI – A powerful, user-friendly utility enabling you to accomplish common administrative tasks.
SharePoint 2013 FBA Pack – A forms based authentication pack for SharePoint 2013. It includes web parts for registering users, changing passwords and password recovery
FBA Configuration Manager for SharePoint 2013 – An excellent tool to take the sting out of configuring FBA (no more editing web.config files!)
Language packs for SharePoint 2013 – Language packs enable creation of sites and site collections in multiple languages without requiring separate installations of SharePoint Server
Brent Ozar Blitz – A free tool to assess your SQL security, health, performance and configuration – ideal for troubleshooting SharePoint performance issues
CardioLog Analytics (free edition) – A web analytics solution for SharePoint
CipherPoint Eclipse – provides transparent SharePoint encryption for SharePoint server farms, including for large enterprises with large and complex SharePoint farms, and multiple locations
SharePoint Feature Administration and Clean Up Tool – The Feature Admin Tool finds faulty FeatureDefinitions and cleanly uninstalls them.
Alt Login – A free feature to restore the ‘Log in as a different user’ functionality in SharePoint 2013
Recovery Manager for SharePoint – Simplify and accelerate granular and disaster-level SharePoint restores with Recovery Manager for SharePoint. Use your existing enterprise or native backups in order to perform granular searches, previews and comparisons with this flexible tool.
SharePoint Color Palette Tool – A free tool from Microsoft to build themes in SharePoint 2013
SharePoint Client Browser – Find hidden lists/items/documents, discover the structure or specific artifact properties