Dubrovnick is lovely this time of year

In late May, Y Combinator-backed start-up AirBnB, which just raised a monster at a $1 billion plus valuation, was revealed to be using what many consider a black hat technique: relentlessly crawling  Craigslist for vacation properties and emailing the posters on these listings to suggest they use AirBnB instead.

The company apologized for the spamming, stating that it was the work of  independent contractors who had been let go. "The Craigslist thing is unethical and against Craigslist's rules but not, as far as anyone can tell, illegal. It's sad and bad and not to be encouraged." This was  "not a tactic we condone or endorse" and "our policy to forbid such actions," said AirBnB.

But AirBnB wasn't about to stop leveraging Craigslists massive classified platform, by far the largest in the world. In fact they have automated the process for users, creating a "promote" button that exports AirBnB posts directly to Craigslist.

Here's an AirBnB post for a place in Williamsburg. And another one. And for those of you too cool for the 'Burg: Bushwick. Cali, where's the love? LA! San Fran? An "entrepreneur's dream!" Chi-town, you down? Hell yeah, North Side! What it is, DePaul? What if you need to get out of town, say, to Croatia? AirBnB's there, too. Note the identical formatting, the subtle omission of AirBnB's brand and the clever links (more info) and (contact me here), that drive users back to AirBnB's main site.

"You're fufilling the promise to the consumer, so if you're not overloading the site with exported posts, I can't see them having a problem with it," said an e-commerce exec who works frequently with Craigslist.

The kicker? Go onto AirBnB and try to create a post with a link back out to Craigslist. Sorry kids, but it's against AirBnB's terms of service to mention any outside service in your posting. All's fair in love and war. And how many start-ups can claim they found funding through the Craigslist Missed Connections?