FORTUNE -- A month ago, Kevin Rose, the founder and former CEO of Digg, built something creepy. He had been nursing an idea that would test the limits not just of how much we wanted to share online, but also how much we wanted to know what others were sharing. So Rose and a friend coded a quick program called Peeka. It featured a "bomb button" that would do more than just share an article with a friend. It would take over her browser window, forcing her to read whatever you bombed. Rose invited a handful of friends to try Peeka, and the reaction from all, Rose included, came clear and came quick. "It's not a good product. It doesn't feel right. It doesn't feel fun. It feels scary," Rose says. It was an idea that simply wasn't working. So, after a few weeks of development, Rose shot it in the head.
"Shoot it in the head" is Rose's favorite way to murder an idea. Last week, when Techcrunch's Sarah Lacy first reported the details of Rose's next startup, Milk Inc., he told her that at Milk, "if something isn't working after four months, we'll just shoot it in the head and start again." A week later, on the phone with Fortune as his dog whined in the background, Rose picked up the revolver again. "We just wanted the flexibility going into this to be able to shoot something in the head if it's not working."