Bicycle helmets are one of those things that expose the irrationality of human nature.

Even though they protect our noggins, they make us look goofy when we strap one on. Worse, they leave our hair a mess when we take them off. Cyclists have been loath to wear them.

But now, helmet designers are using style as an incentive for cyclists to practice better judgment. Safety, meet vanity.

Companies such as Giro and Bern are making cool-looking helmets with "softer, subtler designs," said Ben Morrison, co-owner of the Handsome Cycles shop in the North Loop area of Minneapolis. Target, meanwhile, has collaborated with charity-based design company FEED to create a stylish paisley bicycle helmet resembling skateboarding headgear for $35.

Hold on, though. We like convenience almost as much as we like looking good. Even if you've got a stylish helmet, you still have to carry the darn thing around.

There's a solution for that, too. It's called the Hövding Invisible Helmet. Created in Sweden and made available for purchase in late 2012, this "inflatable bicycle helmet" is worn around the neck and looks like a new wave scarf. When its sensors detect an imminent collision, the Höv­ding swells within a tenth of a second into a kind of gigantic glove that envelopes the user's head.

Basically, it's a bicycle air bag.

Alas, the Hövding has a downside: It's $600 and can't be used again after it inflates the first time.

"That's a little a steep," Morrison said. "At 600 bucks I think I would just carry around a regular helmet."

Andrew Wagaman • 612-673-4645