In Windows Server 2012 you have the ability to change a password from the Windows Security settings. But sometimes this feature can be hard to find if you connect to a Server via a Remote Desktop Connection. This article describes how to open this feature via PowerShell.
In SharePoint 2010 there is a concept called Managed Accounts. You are able to register Active Directory accounts which you can manage via the SharePoint 2010 interface. This article describes how to register managed accounts in bulk.