The grand-daddy of all buy one, give one (BOGO) cause marketing is TOMS Shoes, which I've profiled in the past. TOMS gives away a pair of its alpargatas-style shoes when your buy a pair. TOMS has never advertised heavily, but so great was the buzz that TOMS generated that its founder, Blake Mycoskie, was featured in TV ad on the left for AT&T.
I've also profiled BOGO efforts from HUGO Fragrances, Pampers, LJ Urban which built a house in Burkina Faso when you bought one of their homes in Sacramento, a solar charger called Solio that provided a match for a soldier serving abroad when you bought another.
On April 1, 2009, I even ran a post saying that India's Tata Motors was doing a BOGO for their $2,500 Nano car. It was an April Fool's Day joke that no one ever called me on. I now confess now that I made up the whole thing.
These next BOGOs, however, are no joke.
Buy a men’s tie, either a necktie or bowtie, from Figs and they’ll send a school uniform to a schoolchild in east Africa. They call it ‘Threads for Threads.’
CellarThief.com donates 100 days of clean water for one person for every bottle of wine you buy. The mechanism for how the water donation takes place or where its given is not specified.
Sage Hospitality, a Denver company that owns and manages hotel properties in North America, ran a similar effort meant to encourage volunteerism called 'Give a Day, Get a Night.' (Sorry, but the link is no longer active.)