Volatility be damned—a '90s icon makes a risky comeback.

She claims to have made $500,000 trading stocks, options, and exchange-traded funds in the last eight months. But she cautions: "This is work. This isn't easy."

Stockstill, who ran her own clothing and furniture businesses before deciding to invest full time, is constantly monitoring markets around the world, looking at futures, currencies, and other investments. She is an ongoing student of using various technical indicators to divine the direction of share prices. Bloomberg and CNBC are on in the background in her home office throughout the day. "There's a lot to know," she says. "If you don't understand charts, you can really get killed."

At one point she lost $240,000 in a single week. "Mostly it was me really not paying attention. And my platform crashed. Sometimes that happens when there are so many trades going on. All of a sudden you try to sell and the systems are jammed. You can get hit fairly hard."

Does she ever get scared about the risks she's taking? "I wouldn't use the word scared," she says. "I'd say apprehensive. If some surprising news comes along and you're full in, it's nerve-racking. It can be very intense."

Rockwell, for his part, has moments of high anxiety. On Thursday, as the market was making a big move late in the day, rising more than 850 points from its intraday low, he was trying to exit some short positions and couldn't get his software to function properly. "It was really hectic for about 30 minutes," he says.

Ironically, he says, part of what keeps him going as an active investor is the need to exert some control over his financial life at a time when the global economic situation often seems hopelessly out of control. He admits that the sense of control he feels by following the market's every turn and risking money based on intuition and various mathematical models may be illusory, but he believes it's better than passively relying on experts to do it for him.