Studded tyres are probably the best way to avoid sliding all over the place on slippery, icy roads. But when that layer of snow and ice is gone, they're not particularly friendly to bare asphalt. Nokian Tyres, though, has developed this concept tyre with studs that extend and retract with the push of a button on your dashboard.
To ensure that extending the studs doesn't cause each tire to start slowly leaking air, the mechanisms are all self-contained and sealed so you don't end up running on flats by the time the spring rolls around.
Unfortunately it doesn't seem like Nokian plans to put its new Hakkapeliitta concept tire into production anytime soon. But the company isn't ruling out the chance that it might become a reality one day. Which is particularly good news for amateur secret agents who don't have a well-funded MI6 behind them. [Nokian Tyres via Damn Geeky]