LogMeIn Hamachi2 is a hosted VPN service that securely connects
devices and networks, extending LAN-like network connectivity to
mobile users, distributed teams and business applications. You can
easily create secure virtual networks on demand, across public and
private networks.

Linux beta binary blob from https://secure.logmein.com/US/labs/

This requires the "tun" driver to be built into the kernel or
available as a module- not a problem for Slackware (indeed, most)
kernels.

Provided is a sample rc.d script, /etc/rc.d/rc.d/rc.hamachi, to start
the Hamachi2 daemon. To run it on boot, make it executable with

    chmod +x /etc/rc.d/rc.hamachi

and add the following to /etc/rc.d/rc.local:

    if [ -x /etc/rc.d/rc.hamachi ]; then
      . /etc/rc.d/rc.hamachi start
    fi

Hamachi2 writes its configuration information to
/var/lib/logmein-hamachi.  To modify the server configuration, add
your parameters to /var/lib/logmein-hamachi/h2-engine-override.cfg and
restart the daemon with /etc/rc.d/rc.hamachi restart. Parameters you
can change (in fact, the daemon's current configuration) are listed in
h2-engine.cfg in this directory.

Example /var/lib/logmein-hamachi/h2-engine-override.cfg:

    Conn.DisableUpnp    1
    Ipc.User        vike
    Sock.TcpAddr    192.168.1.33
    Sock.TcpPort    51232
    Sock.UdpAddr    192.168.1.33
    Sock.UdpPort    51232

This config allows the user vike to use the hamachi command for
controlling the vpn. It also disables UPnP for negotiation of
the hamachi listen socket and forces it to the address and port
listed. This is useful when you are willing to do a port forward
yourself, because UPnP can be unreliable.

For more information run the hamachi command without parameters and see
/usr/doc/hamachi-<version>/README.