I have multiple sites configured in IIS7 on my Windows 7 development machine to run on the same port and usually only run one at a time depending on what I\'m working on. I
Adding to Keith's answer, you can perform this remotely using Invoke-Command.
Import-Module WebAdministration
$siteName = "Default Web Site"
$serverName = "name"
$block = {Stop-WebSite $args[0]; Start-WebSite $args[0]};
$session = New-PSSession -ComputerName $serverName
Invoke-Command -Session $session -ScriptBlock $block -ArgumentList $siteName