$HTML = Invoke-WebRequest -uri http://imgur.com/a/y2mt7

$ParsedHTML = $HTML.ParsedHtml

$ParsedHTML.getElementsByTagName("div") | Where { $_.className -eq "post-image-container post-image-container--spacer" } | ForEach-Object { invoke-WebRequest -uri ("http://i.imgur.com/" + $_.Id + ".jpg") -OutFile ($_.Id + ".jpg") }