Akihisa Fujita has always been a night owl. The 32-year-old former bartender spent much of his 20s serving drinks at high-end establishments in Tokyo's Ginza and Yoyogi-Uehara districts, all the while dreaming of owning his own.

But after some thought, he realized it wouldn't be much fun having to serve lots of people he didn't necessarily like every night. It would be better to save enough money to open a bar and have someone else manage it, he reasoned. He knew he couldn't earn that kind of money as a bartender, so a few years ago he swapped his job for another night-shift job, but in a completely different field.

While he still starts working late, around 11:30 p.m., he now works at home, and he works alone. And unlike his previous job, the stakes are extremely high -- he could earn or lose a few thousand dollars in a matter of seconds.