It weighs under a ton, is only 3.5m long, and has a 1.0L, 3-cylinder engine that fairly sips gas. It shifts like butter and, considering it's powered by a glorified sewing machine, it has decent acceleration and top-end speed. And, if you spring for the Czech rebadge, you can get the basic model for less than 10k euros.
But the real killer is that it has almost as much usable interior room as a VW Golf, despite being almost a meter shorter!
My partner and I both come from tall families and, upon delivery of the car, her brother (200cm tall) drove his wife (189cm), me (188cm), my wife (184cm), my father (200cm), and our 3 kids for a spin. It wasn't legal and it wasn't roomy, but no reasonable person would be able to guess that such a tiny car could fit 3 small adults, let alone 5 tall adults and 3 kids.
For those of us who spent far too much of their childhood playing Tetris, the trunk (if you want to call it that) also accommodates 4 full-sized suitcases.
[EDIT] I forgot to mention that it has exposed metal surfaces in the interior (doors, mainly) that are integrated parts of the car. Not only does it look fantastic, each of those panels is one less plastic piece that will eventually require an expensive replacement when it inevitably gets hit/scratched/exposed to too much sunlight/shakes itself to pieces.
I don't know why more cars don't feature this (one review called them "cheap exposed surfaces", as if plastic is somehow fancier), but it's incredibly durable, simple, and attractive.