I had an Opel GT in college. It was a great car and actually handled really well. Mine was only about 10 years old when I bought it and it already had quite a bit of rust. Not long after I bought it, I was driving home from work and it started raining. Soon after the rain started, I noticed that the carpet down by my feet was wet. Since my feet were dry something was up. I reached down and pulled up the carpet and saw road rushing past! Big holes in the floor boards.
The car was actually alot of fun. I put a Weber carburetor on it (the Solexes were crap) and removed the primary muffler and only ran the rear dual-out resonator. It sounded great. The headlight mechanisms were a PITA and the wiring on the car left alot to be desired, but it was pretty cool. Parts were cheap and it was easy to work on.
I'd love to have another one.