OK, for starters, it's not a real flamethrower, which as the name implies, throws flame and is a terrifying weapon of war. The term conjures images of U.S. Marines using the devices to ravage dug-in Japanese soldiers on Iwo Jima during World War II. Military flamethrowers could throw fire at distances of 20 meters or more. It's not even like other flamethrowers you can actually buy for civilian uses like agricultural burns (never mind that in this example, a commercial flamethrower is being used to set fire to cars and living-room furniture.)
Instead, Elon Musk's flamethrower is something like a big Bic lighter, or a propane torch you'd use to caramelize a creme brulee. A really big creme brulee.
You can preorder one at The Boring Co.'s website, which bills it as "Guaranteed to liven up any party!" And "World's safest flamethrower." Safest flamethrower being a relative term, you can also supposedly order a fire extinguisher with it. All of this seems to be for real, as the site sends you to an order cart and order form. Then again, the fine print contains phrases like, "Before shipping, aspiring flamethrower aficionados will be sent a terms and conditions rhyme for review and acceptance," and, "May not be used on Boring Company decorative lacquered hay bales or Boring Company dockside munitions warehouses."
Musk tweeted last night that 7,000 of the flamethrowers have been preordered so far, and the company plans to sell 20,000 of them — which would bring in $10 million.
So again, what does this have to do with digging tunnels? Who knows. Only Elon. But since you can't preorder a car tunnel like you can a Tesla Model 3, this is one way to make a bit of bank. The merchandising potential of a brand called "The Boring Co." is huge, even if it never wins an actual contract for an actual car tunnel. And since we couldn't have predicted a flamethrower, it's hard to know just what will be the next entry in the company's gift catalog.