This made me laugh nostalgically. A Geo Prism was one of my first "$1000 cars" as a kid. Fun little car, but once it hit 40 it started shaking like a tree. I always joked that if I drove it on the highway it would shake itself apart around me and I would end up with suspended in air with only a seat and a steering wheel left, looney tunes style, before plummeting to the ground.

I sold it off for a different $1000 car before it happened, but sounds like that's precisely what happened to you!