Back in the old days, you could have a Genestealer Cult army in Warhammer 40,000, and its senior members were allowed limousines. There was never an official model, but the army list contained this picture:
It's surprisingly difficult to find a model that has the right overall design and the chunkiness of a 40k vehicle. Most WW2 armoured cars look too sensible. However, I stumbled upon this model of an armoured car from the Spanish Civil War, made by the company Minairons:
These things were big. They look rather like a 1920's idea of the future, or perhaps a very primitive batmobile. Perfect for 40k!
I swapped out some of the wheels on the original kit, as they seemed a bit narrow for the feel I wanted. I bulked up the bonnet with Tau parts and added gun pods from an Ork fighta, as they had the same smooth look as the rest of the car. The organic-looking things at the end of the wheel arches and the scrollworked bit above the radiator grille are from Dark Eldar talos kits.
The turret that came with the kit felt a bit excessive (for an alien pimpmobile, which is saying a lot). A sort of pulpit where the Magos could address the masses seemed more appropriate. The one I used came from a High Elf chariot. Again, I chose it because it had a similar organic shape to the main vehicle.
All ready to roll through the mean streets of the underhive. It just needs some crew...