If you want to steal Sparse bicycle lights, you're pretty much going to have to steal the whole bike. The Sparse headlight is called the Spacer Light, so named because it sits beneath the handlebar stem. It features a 3-watt white LED and can be set to on, off, or blink.
The 1-watt Sparse taillight slips onto the seat post. As with the Spacer Light, you would have to start removing parts of the bike in order to steal it. Both lights are made from die-cast aluminum to stand up to the elements and the jostling of biking.
The lights use rechargeable batteries and come with a 6-foot micro-USB charging cable and wall adapter. This is a solution that will work best for people who park their bikes near a wall plug. The batteries have about a 4-hour life before needing to be juiced up.
One downside to Sparse is the expense. A single taillight goes for a $50 pledge while a single headlight is $75. You can get the set for a $120 pledge. That hasn't stopped the company's Kickstarter from already topping its $45,000 goal.
For some people, Sparse could be significantly cheaper than constantly replacing less-expensive lights. They also have the advantage of looking good. The sleek design is way slicker than the many chunky light options already available.
The Sparse lights are currently in prototype form, but the Kickstarter money will be used to get them into mass production. I can see the appeal. Whenever I lock my bike up outside a store at night, I wonder if my lights will be there when I get back.