For the benefit of those who are automatically going to say "uncool because four cylinders," or "uncool because FWD" let me try to suggest why those things aren't really a problem here, and why in some ways it makes it even cooler.
First of all, it is a fantastic car to drive. The steering feel is brilliant, and the throttle response and gearchange are genuinely better than anything else I've driven. Back in the '80s, the 205 had a reputation for scary amounts of lift-off oversteer, which reulted in many examples flying backwads through hedges. Modern tyres have eased this silghtly (I've had it happen to me twice; once intentially, the other less so..)
Exciting to drive, to the point of being intimidating? Cool
For those who think that 130hp is not enough power, remember that it weighs nothing. Depending on whose figures you believe, it'll hit sixty between 7.5-8 seconds, which can hardly be considered sluggish. That low weight means that on the right road it has a genuine giant killing quality, too, as the owner of a Maserati GranTurismo I once came across found out to his cost
A car which can humble more expensive and "faster" machinery? Cool
Beyond the ability of the actual car, the 205 GTi is rare these days, too. It turns heads simply because you don't really see them anymore.
Rare? Cool
The 205 is also a car with a genuine motorsport pedigree, which can trace it's roots back to one of the coolest forms of motorsport, Group B rallying. And then there were the Pikes Peak versions, too.
Motorsport pedigree? Cool.
Anything that makes it uncool? If some people still get a whiff of chaviness about the GTi, then I can understand that to some degree - anyone growing up in the mid-to-late nineties will have seen Max Power cover cars painted bright orange and dressed in horrific body kits. Thankfully nearly all of those cars have long since died off, just like (in my opinion) the connotations that go with them.
I know this is more subjective, but I love the way it looks - the styling is clean, well-proportioned and with just the right amount of agression, the little pepper pot wheels look great, and it's teeny size makes you realise just how bloated modern cars have become. Even the interior is surprisingly pleasant for an '80s car. Yes, the build quality is flaky, and out of the three electrical devices in my car, I had to fix the central locking, one of the windows is tempremental, and the clock tells whatever time it pleases. But nearly all of that is irrellevant, because any car that makes any drive feel like an exciting event must be cool.
I'm watching how you all vote very closely