On Monday we gave you a list of brands doing cool things on Vine, Twitter‘s six-second looping video app. Today we have to add Clorox‘s Green Works to that list for their St. Patty’s day-themed campaign urging fans to “go green” by playing charades. Tweeters who guess each charade correctly will then be entered to win $500 (which they will presumably use to buy everyone a round tomorrow night). And yes, this is Lance Bass (aka the taller Justin Timberlake).

Rebecca Boston Sobel, head of PR and digital strategy for Green Works, explains:

With the recent relaunch of our marketing campaign, we’re focusing mostly on creating digital activations that are timely, deliver on our core message – that green can be for everyone – and ultimately fun for consumers. Playing St. Patty’s Day charades on Vine for a chance to win a pot of “green”  was an engaging way to highlight that you don’t have to “put on a charade to be green” and delivered across the board.

So another step in the evolution of Vine as a PR tool. What do we think?