All Your Base Belong to RapLeaf
They essentially give you demographic information of your customers so if your a small company you can get info that was typically only available to big companies.
From RapLeaf, "Rapleaf is a San Francisco-based startup with an ambitious vision: we want every person to have a meaningful, personalized experience – whether online or offline. We want you to see the right content at the right time, every time. We want you to get better, more personalized service. To achieve this, we help Fortune 2000 companies gain insight into their customers, engage them more meaningfully, and deliver the right message at the right time. We also help consumers understand their online footprint.
At our heart we are an internet technology company that builds innovative products to compile and analyze large amounts of information."