What's the best way to spend $100/€90/£70 on your car?

Tesla owners be like, “just upgrading my P85D to P90D, bruv”

Pads or discs

Windscreen wipers, washer fluid, coolant, oil, filters, car wash, new bulbs, wax

Magnaflow sport Cat
1)Better fue economy
2)more power
3)better sound

A mini moto?

Tissue paper to stop crying over the fact you swapped an s2000 with a polo

Buying a solid engine mount to complement the other two I have.

A proper tune-up. Doing a good servicing to your car is probably one of the best ways to make sure that it will keep being reliable.

Fill up and in my current situation oil change

pop-up headlights!