Yeah, I was asked to model a graphics program in an interview and got into a argument about why circles should not be a subclass of ellipse. I explained that,

Yeah, I was asked to model a graphics program in an interview and got into a argument about why circles should not be a subclass of ellipse. I explained that, yes, mathematically it's a degenerate case, but in a graphics package circles have different algorithms and different user interfaces. They actually have more in common with squares than ellipses. After about 10 minutes of no progress, I suddenly realized I would be working with and for idiots so I excused myself from the rest of the process.