Havas has a crowdsourced department : Havascrowd

Havas has a crowd sourcing do-dah 'powered by Victor & Spoils' called havascrowd.com. OOoh, shiny and pretty and I'm surprised it's not on Vine yet. What does it do? It connects all of Havas to all of Havas so that all of Havas can crowdwork together. I think, I'm not sure, I'm blinded by ®'s.

Havas is dedicated to getting clients to the future first. Beyond pioneering Creative Business Ideas® and Social Business Ideas®, we are now offering the full creative and strategic capabilities of the Havas network — all in one place. So if you are part of the Havas family, join the crowd. And if you want to harness the power of the entire Havas global network, hire the crowd. Let's get to work.

Catch - you already have to work for Havas when you sign up here. See they're asking you for your age at the signup page, and you know that's not legal in the USA if they were going to hire you. But since you're already hired, that's A-OK. Not quite understanding why the people already employed by Havas aren't automagically joined already, but perhaps Havas feels that time spent filling in forms with ones last five employers is something that clients don't mind being billed. Why be efficient when we can be redundant.