Until the torrent archive file be available for DEFCON22 run the below bashfu to download all ppt/pdfs:

wget https://www.defcon.org/html/links/dc-archives/dc-22-archive.html --no-check-certificate | grep dc-22-presentations dc-22-archive.html | awk -F "href=\"" '{print $2}'| awk -F "\"" '{print $1}' | sed 's/\.\.//g' | sed 's/\/\//https:\/\/www.defcon.org/g' | xargs wget

by