Poised to become $1.5 billion a year market according to eMarketer, behavioral targeting - used by Snapple in a test - found an unexpected affinity group for Snapple's new premium line of  "Good for You" green teas, which the company assumed would target fitness nuts (via AdAge).

To test that theory, MEC Interaction worked with Tacoda to create a six-week behavioral-targeting campaign in late third quarter and early fourth quarter to identify the behavior of the type of person most likely to visit the website.

Surprisingly, the people who responded best to the campaign weren't sports fiends at all, but those interested in arts and literature. People who traveled also responded well - especially those who traveled internationally.

Though priced 20-30 percent more than regular online ads and limited in supply, targeting customers by behavior rather than demographic is actually a lot closer to the way marketers buy TV, said Dave Morgan, chairman of Tacoda.