How to find WMI information with PowerShell

"Windows Management Instrumentation (WMI) is the primary management technology for Microsoft® Windows® operating systems. It enables consistent and uniform management, control, and monitoring of Windows computers. Based on industry standards, WMI allows us to query, change, and monitor configuration settings on desktop and server systems, applications, networks, and other components. We can write scripts that use the WMI Scripting Library to work with WMI and create a wide range of systems management and monitoring scripts."

Well, that's nice, but how to get around in this "WMI world" with PowerShell. It's not that hard at all.