This will cover Powershell.
If you rather would like information on opening an administrative command window, read this thread.
I somehow have to stop wondering how little curious people are when it comes to exploring a new operating system. The "Open Powershell Window Here as Administrator - Context menu" is actually not needed, but I was asked if I could create it anyway to meet a convenience demand (iow, we do not want to do anything but what we're used to)... and so I did rework the script to start powershell.exe as administrator instead of the command prompt (cmd.exe).
Why is "Open Powershell Window Here as Administrator" not needed?
That question is easily answered, it is already present and I will show you where using two screenshots.
This is a snap of explorer open at the Powershell\1.0 folder with one directory selected as shown.
If you click on the File tab, you will have access to open a Powershell in the selected folder, either as administrator or in the context of your user as shown. If you look at the screenshot, you will also notice that the choice to open a command window is also present.
I still would like to have the choice of right-clicking a folder in explorer.
Here, enjoy! It is all on me:
Uninstall registry script also included.
Do keep in mind that this replaces "Open command window here as administrator" and so you will have to choose which choice you would like to have in the context menu.
It is possible to add both, but it was out of scope for what I was asked to do. If you would like to have both, update the thread and I'll see what I can do.
For more information, please look at the thread for opening an administrative command line linked at the top.