Simple UAC Prompt for the Windows Command Line.

uac.cmd

@echo off
set __COMPAT_LAYER=RunAsInvoker
choice.exe /N /C YN /M "Elevate? (Y/N?) > "
if %errorlevel% == 1 (
    echo Elevation Granted!
    start /b %*
    exit /b 0
) else (
    if %errorlevel% == 2 (
        echo Elevation Denied!
        exit /b 1
)
)

uac.ps1

$ENV:__COMPAT_LAYER = 'RunAsInvoker'
choice.exe /N /C YN /M "Elevate? (Y/N?) > "
switch ($LASTEXITCODE) {
    1 { Write-Output "Elevation Granted!"; Invoke-Expression "$([string]$args)" }
    2 { Write-Output "Elevation Denied!" }
}