Mod #5: Phone Pouch
The Problem: Like most ND Miata drivers, I generally keep my phone in the little cubby next to the USB ports. But when accelerating rapidly from a standstill (aka "hard pull"), the phone will slide out, often falling into the driver's side footwell and sliding around some more. That's not ideal, especially since being distracted by trying to catch your phone mid-acceleration is not exactly safe.
The Solution: I've velcro'd a pouch to the side of the transmission tunnel, right next to my right leg. I affixed it with velcro (the hook side, which sticks to the interior carpet nicely). This also frees up the cubby for other things that hopefully won't slide out.