Not a "car" that you could take on the Interstate per se, but those Gem cars that TPiR offered about 20 years ago were pretty fugly.
Living just outside a large senior community in Florida, I've seen more than a fair share of GEM cars. They are too small and slow for the roads, and too big and wide for the golf cart paths. The community allows them on the golf courses provided that the tires are a specific size and weight. But I can also see why the GEMs are popular here -- a senior uncomfortable with driving a regular car at their advanced age but determined to keep their license would see the vehicle as an alternative to simpler golf carts.
As far as the other cars listed here -- my parents had a Dodge Omni in the early 80s. By the time it it 40,000 miles, it would randomly stall in the middle of the road or highway (nearly started a multi-car chain reaction crash when the engine stopped in the middle of the PA Turnpike). After months of short-term fixes, we got a new vehicle.
Perhaps not the worst car offered, but there was a time in the mid-90s on TPIR where games not known for being "car games" (Safe Crackers, Cliff Hangers, etc.) started offering a vehicle as its big prize. And it was the same car -- the Ford Aspire.
The Aspire was a replacement for the Festiva that, for the most part, had little to no available options with a 0-60 time of just over 16 seconds. As a result, it was dirt cheap as far as new vehicles went (I believe the prize copy referred to it as a car for the budget-conscious shopper or something similar), and TPIR tried to give the car away on essentially every game on its roster. I presume it was called the Aspire because it aspired to actually be an acceptable vehicle
JD