Here's something from the MSDN Script Center (converted to KiX):

code:
$objNewOU = GetObject("LDAP://OU=Finance,DC=fabrikam,DC=com")
$objMoveComputer = $objNewOU.MoveHere ("LDAP://CN=atl-pro-03,CN=Computers,DC=fabrikam,DC=com", "CN=atl-pro-03")