Search and install SlackBuilds. More information: http://slackermedia.info/handbook/doku.php?id=slackbuilds.
sport for the first time:sudo mkdir {{[-p|--parents]}} /usr/ports && sudo rsync {{[-av|--archive --verbose]}} rsync://slackbuilds.org /slackbuilds/$(awk '{print $2}' /etc/slackware-version)/ /usr/ports/
rsync:sudo sport rsync
sport search "{{keyword}}"
sport check {{package}}
.info files of a package:sport cat {{package}}
sudo sport install {{package}}
sudo sport install $(< {{path/to/list}})