There is something about "chimera" cats that really tickles people's interest. All cats are beautiful in their own way, but we are so used to asymmetry being the norm in nature that a perfectly straight line down a feline's face is fascinating.
Chimera cats are relatively common, since they are simply the result of two embryos merging in the womb to create a kitten with cells from two different sets of DNA. In fact, most tortoise shell cats are chimeras.