-In-car champagne fridge (Rolls-Royce, Bentley, Maybach, Range Rover, & even Ford?)
Rolls-Royce, Bentley, Range Rover, and Maybach all have this optional on at least one of their products. Ford even offers a less elegant variation of this in the Flex crossover (but it isn't nearly as cool). Very pointless, but if you can afford cars of this class, you probably won't care at all.
-Rolls-Royce bespoke paint
Rolls-Royce offers this on their cars, and it's basically their way of saying: "If you want, we can paint your Phantom limousine the color of your favorite tie." Stupid? Yes. Impractical? Yes. But would you want your $500K Rolls-Royce any other way?
Bentley now offers this on the Flying Spur, and I think the only really "special" thing about it is that it costs $34,995 (lots of cars have metallic paint). Oh well...
-Maybach granite interior trim
This was offered on the Maybach range (57, 62, 57/62S, Guard, Zeppelin, Landaulet) and cost a whopping $60,000. The only thing I find wrong with this is that you could buy a used 2012 Mercedes-Benz CLS550 with $60K, so why spend it on something that is already decadent enough?
-Aston Martin Jaeger-LeCoultre AMVOX2 transponder watch
This was optional on the now-defunct DBS, and all it really is is a really nice watch that can unlock the owner's car. Cool? Yes. A tad overpriced at $37,900? Yes, especially for a watch that has more in common with the upcoming Apple watch (which will be able to unlock hotel room doors) than the car it's sold with.
-Nissan GT-R Spec V Brakes
On your own GT-R, you can fork over $50,000 for a "stellar" set of carbon-ceramic brakes. In my opinion, they seem a little unnecessary for daily usage, such as going to the grocery store, which should never include surprise under-100-feet 60-0 testing.
-SRT Viper "Striker Red" Paint
For $14,000, SRT will paint your very own Viper in a special shade of red, which, to me, looks good, but inappropriate on a Viper (come to think of it, it would great on something like a Mercedes-Benz S600 Pullman).
-Lexus LS600HL Executive-Class Seating
Ever wondered what to spend $14,600 on? Well, look no further, because Lexus offers an option on the LS sedan that turns the backseat in to a first-class airplane on wheels. In this case, a "first-class airplane on wheels" looks like a refrigerated coolbox, individual reclining-massage seats, as well as a Blu-Ray player/drop-down display screen.
Infiniti QX80 Blind Spot Warning System
This may very well be the most practical option on this list, but is ridiculous nonetheless. Now, every soccer-mom can be sure that even while they're texting and driving, they will always know if a car is pulling up alongside them, and for only $12K....
-Porsche 918 Spyder Magnesium Wheels
Even though I am 100% sure everyone who can spend over $800,000 on a car won't care about the price of the options, I'll tell them anyway. The "magnesium" wheels you can get on the new Porsche 918 cost $32,500, which is more than two Kia Rios combined.