With a net worth rivaling the GDP of many small countries and a penchant for a lifestyle that’s equal parts Tony Stark and Thomas Edison, Elon Musk must be a very difficult person to shop for during the holiday season. But even jet-setting, reusable rocket-designing, tunnel-boring billionaires can never really have enough insanely expensive one-off tech, so for anybody looking for a gift guide for that special member of the 0.00001% class in their lives — looking at you Mera — here are seven ideas that will break the bank. Although the people you’re buying the gifts for own it anyway, so it’s fine.

1. The Ultimate Batcave Home Theater (Est. Cost: $2.5 Million) 

Image: Elite HTS

Here’s a cold, hard fact: Tech billionaires like Musk are always nerds. So any one of them would be more than happy to have this Ultimate Batcave Home Theater in their immense Bay Area bungalow. The Batcave theater is Dark Knight themed, and comes with a life-size Batmobile, a stainless steel elevator, a fireplace, and four Batsuits. Because duh, you’re not going to have just three Batsuits. Elite HTS, the company offering the Batcave theater, says it will also soon be working on an Iron Man version. Wonder who that could be for…

2. Aston Martin’s “Project Neptune” Submersible (Est. Cost: $4 Million) 

Image: Triton / Aston Martin

Yes, Elon Musk really did spend a tick below $1 million to buy the Lotus Esprit-based submarine that was used in the James Bond film, The Spy Who Loved Me, but he’s also said publicly that he plans to transform it into a real car-sub combo with a Tesla power train. Until that project’s finished, why not purchase a stand-in submersible made by Aston Martin and submarine manufacturer, Triton. The Aston submersible is still in the concept stages, but it’ll likely be able to carry three people and dive to 1,650 feet.

3. Personal Passenger Drone (Est. Cost: $300,000) 

Although Musk has explicitly said on multiple occasions that he doesn’t think flying cars will be a scalable solution for traffic problems — hence all the boring — that’s no reason not think about getting him, or a tech billionaire like him, a personal passenger drone. Passenger drone maker Passenger Drone (which is kind of like a computer maker being called “Computer” right?) offers a passenger drone with “fully autonomous flying” and the ability to carry two people for up to 25 minutes — definitely reasonable for dodging the normal L.A. commute. No cost is given by Passenger Drone for its passenger drone, but a similar drone by maker Ehang is estimated to cost $300,000.

4. A Bulletproof Suit (Est. Cost: $20,000)

Image: CBS This Morning

Musk, like any globetrotting billionaire, has to travel to some odd places around the world for business, and be around some very high-profile figures. For any dust-ups that may occur there’s a bulletproof suit, offered by Toronto-based custom-suit maker Garrison Bespoke. Bespoke spoke with CBS This Morning about the suit, and said that it’s been requested by those who work internationally in diamonds or oil. And while it may be a bit more James Bond than Tony Stark, it still may be a good little closet item to keep on the company jet in case things get nasty.

5. DORNBRACHT Shower (Est. Cost: $32,000) 

During a detailed AMA on Reddit, Musk was asked what daily habit he believed had the largest positive impact on his life. His answer was one word: “Showering.” If that’s not a hint for a holiday gift, then electric cars aren’t the way of the future. To that end, #5 on the list of adventuring tech billionaire gifts is the “Sensory Sky” shower by Dornbracht, which, according to the company, “creates a multi-faceted, harmonious play of colours, fragrances and water types — for a unique shower experience that stimulates all the senses.” And really, it’s a miracle anybody can get along cleaning themselves without different water types.

6. Giant Mech Toy (Est. Cost $200 Million) 

You know when you were a kid and your friend got something cool, so you had to get that exact same cool thing to keep up? We’re going to guess that kind of consumerist rivalry also exists amongst the super wealthy. And what better way to help Musk eat space competitor Jeff Bezos’ lunch than buying him the giant mech Bezos piloted at MARS Conference 2017? The mech, made by South Korean tech company, Hankook Mirae Technology, is 13 feet tall, weighs 1.5 tons, and literally makes the ground shake when it moves. The smiles this beast would be responsible for make $200 million seem like chump change.

7. SpaceX Trip to the Moon (Est. Cost: $175 Million Per Seat) 

Image: NFarmer

Back in February, SpaceX announced that it would be taking two passengers on a trip around the Moon — something that hasn’t happened since the Apollo astronauts first went there. But you know who else hasn’t been in space yet? Elon Musk. And really, when everything’s said and done, nobody gets to keep the gadgets or the toys or the bulletproof suits. All we get to keep are our memories. And what better memory than flying around the Moon in a rocket that your own company built? The Verge spoke with experts who estimate a ticket would cost $175 million, which means this may be one of those gifts that Elon will have to buy for himself.

What do you think about these gift ideas for Musk and other tech-adventurer billionaires? Would you purchase any of these insane items if you had the money? Give us your thoughts in the comments below!

Feature image: Aston Martin / Triton