SlackBuildsOrg/network/windscribe

Windscribe VPN is a Canada-based provider that promises to help you 
browse the web privately. It contains a set of tools that work 
together to block ad trackers and web beacons, restore access to 
blocked content and help you safeguard your privacy online.
You can use Windscribe for free, for as long as you like.
With a confirmed email address you get 10GB/month of data
and access to over 10 countries.

The following can be used to start/stop Windscribe automatically:
/etc/rc.d/rc.local
  if [ -x /etc/rc.d/rc.windscribe ]; then
    /etc/rc.d/rc.windscribe start
  fi

/etc/rc.d/rc.local_shutdown
  if [ -x /etc/rc.d/rc.windscribe ]; then
    /etc/rc.d/rc.windscribe stop
  fi