Find home items where a rendering has 1 or more rules applied using Sitecore PowerShell Extensions.

Find-Renderings-With-Rules.ps1

$device = Get-LayoutDevice -Default
$sites = [Sitecore.Configuration.Factory]::GetSiteInfoList()
foreach($site in $sites) {
    $isTrackingEnabled = [Sitecore.MainUtil]::GetBool($site.Properties["enableTracking"], $true)
    if($isTrackingEnabled -or [string]::IsNullOrEmpty($site.TargetHostName)) { continue }
    $homeItem = Get-Item -Path "$($site.RootPath)/$($site.StartItem)".Replace("/sitecore", "master:")
    Write-Host "Checking $($homeItem.ItemPath)"
    foreach($rendering in $homeItem.Visualization.GetRenderings($device, $false)) {
        if($rendering.Settings.Rules.Count -le 0) { continue }
        $rendering
    }
}