This finds and recycles SharePoint list items. Also an example of grouping items.
$web = Get-SPWeb -Identity https://xxxx
$list = $web.Lists["Archive"]
$AllDuplicates = $list.Items.GetDataTable() | Group-Object title | where {$_.count -gt 1}
$max = $AllDuplicates.Count
#Retrieve all event receivers associated with the list
$list.EventReceivers | Select Id, Type, Assembly, Class
$confirmation = Read-Host "press any key to continue......."
foreach($duplicate in $AllDuplicates)
{
$items = $duplicate.group | Select-Object -Skip 1 | % {$list.GetItemById($_.ID)}
foreach($item in $items)
{
$item["Title"]
$item["Title"] | out-file "f:\temp\dupsdeleted.txt" -append
$item.Recycle()
}
if($max -gt 0){
Write-Progress -PercentComplete ($count / $max * 100) -Activity "$count duplicates removed" -Status "In Progress"
}
$count++
}
$list.EventReceivers | Select Id, Type, Assembly, Class