Here's an initiative from Kotex that uses Pinterest. Not only are they the first ones out of the gate with a campaign capitalizing on the new-ish platform - but it's a prime example of using social media to connect with many, by only touching a few. Kotex created individualized gift boxes for women based on their Pinterests.
At first glance that seems like a hugely costly initiative. How can a big company send out one of a kind gifts? Well, they only sent out fifty, but the impressions they generated far exceeded their initial investment.