Defictionalization: Hot Wheels had quite a lot of completely original and often downright outlandish designs such as the Twin Mill, first released in 1969, a Cult Classic in the Hot Wheels line-up that has even been produced in several different scales. In 2001, a "1:1-scale" Twin Mill was presented. The builders went all the way to make it both accurate and cool, so instead of a mock-up, they made it a fully driveable car. Since the Twin Mill models lack doors, the full-sized vehicle got a flip-top. Also, both engines are fully functional, connected to the drivetrain, built with performance parts, and the superchargers aren't dummies either. Since it was built for show, it was never dynoed, and so the power output had to be estimated as something between 1,400 and 1,800hp altogether, also because 502cui big blocks were necessary to stay in scale. Last but not least, it's street-legal.
Some castings are an inversion of this. The Hot Wheels Legends Tour is a showcase of custom rides made by roadheads. The grand prize winner will have their winning ride made into a Hot Wheels Diecast for the following model year. Aside from that, the 2005 Ford Mustang SEMA is based on the real life car made in collaboration between Hot Wheels and Action Vehicle Engineering for the 2014 SEMA show. It was later made into a casting for the 2016 line. Hot Wheels didn't even stop there.
Dueling Works: Hot Wheels used to have one with British-originating Matchbox before Mattel bought that brand in 1997; they've been sister brands ever since, with Mattel maintaining their distinct differences.
In Memoriam: The 2022 model line is dedicated to Hot Wheels designer Ryu Asada, who passed away in 2021 from cancer. Several castings made by him in that lineup appear with a "Ryu's Rides" insigna featuring his signature.
The Kiddie Ride: An unknown company has made several kiddie rides based off of the Hot Wheels cars.
Kids' Meal Toy: This franchise is one of the most common boy toys for McDonald's Happy Meals, and is usually paired opposite Barbie for girls.
As of 2015, Mattel can no longer produce Ferrari castings after the licensing rights to them expired that year.
Some other castings that weren't Ferrari also fell to this fate for other reasons, like with the original Bad Mudder from the 1998 First Editions series. It was originally based on Robby Gordon's 1997 Ford F-150 Baja Truck he used in the 1997 season. Because it was extremely similar to the real life car, it was discontinued after the debut release due to licensing concerns. These one time castings are often referred to as "One Hit Wonders" in the collector's fandom, making them rare to find.
What Could Have Been: The aforementioned Twin Mill should have been brought to full scale by Chip Foose, the same guy who later designed the "neo-classic" 1967 Shelby Mustang G.T.500 "Eleanor" for Jerry Bruckheimer's Gone in 60 Seconds (2000). He did start working on it, but the company he worked for went belly-up during the project (which kind of allowed him to make "Eleanor" in the end), so the full-scale Twin Mill had to be completed elsewhere.
was presented. The builders went all the way to make it both accurate and cool, so instead of a mock-up, they made it a fully driveable car. Since the Twin Mill models lack doors, the full-sized vehicle got a flip-top. Also, both engines are fully functional, connected to the drivetrain, built with performance parts, and the superchargers aren't dummies either. Since it was built for show, it was never dynoed, and so the power output had to be estimated as something between 1,400 and 1,800hp altogether, also because 502cui big blocks were necessary to stay in scale. Last but not least, it's street-legal.