Brain hacking--experimenting with supplements and physical techniques to boost alertness and productivity--sounds like something you wouldn't want to attempt without a medical professional nearby, and maybe not even then. But you're already doing it, says Nootrobox founder Geoff Woo, whose Andreessen Horowitz-funded and San Francisco-based startup makes supplements purported to sharpen brainpower. "This," he says, holding up an iPhone, "is like a dopamine drip into your brain. For whatever reason, it seems scarier when you're more directly affecting human body parts, but your mind is half on a computer already."

The entrepreneurial world is suddenly crawling with those manipulating their brains and bodies, seeking incremental productivity gains. Their methods range from extremely eccentric to "Hey, maybe I should try that too." If you're wary of weirder approaches but remain curious as to what might work, squeezing more productive hours from your day could be as simple as fasting, which proponents say can make your mind clearer on top of helping with weight control. Once a week, all eight employees of Nootrobox stop eating for 36 hours. They adopted this ritual after coming across research suggesting intermittent fasting can stimulate the growth of new brain cells and enhance the activity of genes that play a role in extending lifespan. (Their enthusiasm outpaces that of more traditional researchers on the topic--which is generally par for the course with brain hacking.)

Or try changing your sleep schedule. Sumaya Kazi, the CEO of marketing technology startup Sumazi, typically sleeps from 3 to 4 p.m., 11 p.m. to 3 a.m., and 5 to 8 a.m. That schedule unlocks distraction-free hours in the middle of the night, allowing her to power through tasks like compiling presentations after full days of meetings. Before Sumazi, she says, such sleeping techniques enabled her to launch online media startup the Cultural Connect while leading social media at Sun Micro­systems: "I was able to find the time and not think twice about it."

It's unclear whether poly­phasic sleep offers benefits beyond making nights more productive, and it's worth emphasizing that many hacking methods are unproven. Some products are just scienced-up versions of things you probably already use--like Nootrobox's Go Cubes, which are basically caffeine gummies. Other items from the company also look suspiciously familiar to University of California, San Francisco, professor of pharmacy Candy Tsourounis. "Products like these enter the marketplace all the time," she says, unimpressed. "They're called 'dietary supplements.'" And some methods sound more recreational than disciplined, like LSD micro­dosing. (Proponents say it stimulates creative problem-solving; LSD remains illegal in all 50 states.)

But the absence of hard proof doesn't stop the intrepid from experimenting. Alex Debelov, founder and CEO of the ad-tech startup Virool and a disciple of productivity guru Tim Ferriss, uses internet-connected Philips Hue LED light bulbs that can match the lighting in his home to his desired mindset. He toggles between different combinations of color and intensity depending on whether he's doing focused work, reading, or relaxing. The approach is not necessarily bunk: A recent study led by a postdoctoral fellow at the University of Arizona showed that people exposed to a certain wavelength of light had faster reaction times. Also, as you'd imagine, all those colors look nice, too.