$1 → $1M · 5 tiers

Wheel.

From a wooden disc that changed civilisation to a single carbon-fibre wheel that costs more than most cars.

Plastic toy car wheel

Material: Injection-moulded ABS plastic, 28 mm diameter, friction-fit on a steel axle.
Function: Spins. Falls off. Gets lost under the sofa within a week.
History: The first toy cars with detachable plastic wheels appeared in the 1960s. Made with scrap but with soul — entire factories in Shenzhen run on the assumption that a kid will lose this wheel and the parent will buy a whole new toy.
What bumps the price: Soft rubber tread instead of hard plastic (+$0.20), branded car (+$0.50), being a Hot Wheels collectable from 1968 (+$3,000).

Material: Cast aluminium alloy, 17-inch diameter, machined finish, OEM-spec for a mid-range sedan.
Function: Bolts onto your car. Holds a tyre. Doesn't bend on potholes.
History: Cast aluminium wheels replaced steel in the 1970s because they're 40% lighter — better fuel economy, better handling. The metallurgy is direct heritage from World War II aircraft engineering.
What bumps the price: Diamond-cut finish (+$30), gloss black powder coat (+$40), genuine OEM badge instead of aftermarket (+$25).

Material: Forged aluminium centre, polished split rim, individually torqued bolts, weighing ~2 kg less than the cast equivalent.
Function: Same as a stock wheel — but every car nut at the meet will compliment them.
History: BBS RS wheels became iconic on 1980s Porsches and AMG Mercedes. Three-piece construction allows refurbishment forever; original 1986 sets are still being polished and resold today.
What bumps the price: Date-stamped originals from 1986 (+$400), gold centres instead of silver (+$200), full set of four (+$3,000 if matched lip widths).

Material: Hand-laid carbon-fibre rim, forged aluminium centre, titanium hardware, weighing 5.2 kg per wheel — half a stock alloy.
Function: Drops 0.3 seconds off your lap time at Laguna Seca. Costs more than the lap fee.
History: HRE Wheels, founded 1979, started supplying Formula 1 teams in the early 2000s. The carbon-fibre weave on the rim is the same process used on a Bugatti Chiron's air intakes.
What bumps the price: Carbon weave matched to the car's body panel (+$1,500), centre-lock conversion (+$2,000), full set of four (+$30,000).

Material: Single carbon-fibre wheel for an Aston Martin Vulcan AMR Pro, forged from one billet of titanium, set with 480 lab-grown Ekati diamonds along the spoke pattern, finished in mirror-polished palladium.
Function: One of four wheels on a one-off bespoke hypercar. Can be driven, technically. Will be displayed in a climate-controlled vault, practically.
History: Bespoke wheels for one-off hypercars are commissioned with the car itself. Aston Martin's Q division and Pagani Huayra Roadster BC owners have requested wheels with diamond inlays since the 2010s — usually at the buyer's insistence and expense.
What bumps the price: Matching set of four wheels (+$3M), gold-plated lug nuts engraved with the buyer's initials (+$80K), a signed certificate from the carmaker's chief engineer (+$50K).