 Anti-smoking advocates see it as a gateway product for kids. It's called Sensa, a nicotine-free e-cigarette. Tobacco maker R.J. Reynolds says it'll market the product to adults 21 and older, but the campaign for tobacco-free kids isn't buying it. It says with fun-sounding fruit flavors like watermelon-frost and berry fusion and brightly colored packaging, the product is targeted at kids and teens. The Wall Street Journal says regulating Sensa would be something of a gray area since it doesn't contain nicotine.