Tesla is giving the public a chance to drive a tunnel-boring machine, as part of CEO Elon Musk’s new Boring Company venture. The new company is currently digging its first tunnel beneath the SpaceX offices in southern California, with future plans to build tunnels for hyperloop systems that connect cities several layers deep. Vehicle owners that refer their friends to buy a Tesla will have the chance to pilot a machine.

“You’ve unlocked the second secret level,” the notification shared with Teslarati reads. “Share your referral code to give 5 more of your friends free unlimited Supercharging and $1,000 off a new Model S or Model X. Once all 5 take delivery, we’ll give you the opportunity to drive an electric tunnel boring machine with The Boring Company in Hawthorne, CA.”

The Boring Company’s first intended project is a tunnel running underneath Los Angeles, which will link Los Angeles International Airport to Culver City, Santa Monica, Westwood, and Sherman Oaks. Alongside this, Musk claimed in July that he had received “verbal govt approval” to build a hyperloop between New York and Washington, D.C..

Musk plans to build a car elevator to lower vehicles into the tunnel, propelling them along on a skate. Here’s a concept video of how this may work in practice:

The ninth and current iteration of Tesla’s referral program started in May of this year. It’s become something of a staple of the Tesla community, first starting in July 2015, and the current program will run until December 31st of this year. Every customer referred via this iteration will receive the $1,000 discount and unlimited use of the high-powered supercharger network, which promises to charge a Tesla in under an hour at one of over 6,000 charge points worldwide.

The second level builds on the initial set of rewards. The first round of qualifying referrals offered a staggered list of rewards:

  • One referral: a Tesla Model S for kids.
  • Two referrals: priority ordering for the Tesla solar roof.
  • Three referrals: exclusive 21-inch arachnid wheels.
  • Four referrals: special edition red Powerwall 2 for storing renewable energy.
  • Five referrals: an invitation for the recipient and one guest to see the unveiling of the Tesla Semi truck on September 28.

The first level also included prize draws for tours of the SpaceX facilities and Ludicrous P100D performance edition Model S cars, the latter of which probably handles a bit smoother than the digging machine.

Photos via SpaceX