There is a great community wiki comment that demonstrates adding a context menu entry (though, without admin rights). How would you change the registry keys or the following .reg file to open PowerShell with Administrator privileges?
Windows Registry Editor Version 5.00
;
; Add context menu entry to Windows Explorer background
;
[HKEY_CLASSES_ROOT\Directory\Background\shell\powershell]
@="Open PowerShell window here"
"NoWorkingDirectory"=""
[HKEY_CLASSES_ROOT\Directory\Background\shell\powershell\command]
@="C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe -NoExit -Command Set-Location -LiteralPath '%V'"
;
; Add context menu entry to Windows Explorer folders
;
[HKEY_CLASSES_ROOT\Directory\shell\powershell]
@="Open PowerShell window here"
"NoWorkingDirectory"=""
[HKEY_CLASSES_ROOT\Directory\shell\powershell\command]
@="C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe -NoExit -Command Set-Location -LiteralPath '%V'"
;
; Add context menu entry to Windows Explorer drive icons
;
[HKEY_CLASSES_ROOT\Drive\shell\powershell]
@="Open PowerShell window here"
"NoWorkingDirectory"=""
[HKEY_CLASSES_ROOT\Drive\shell\powershell\command]
@="C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe -NoExit -Command Set-Location -LiteralPath '%V'"