Brett is the co-founder of Scout, which combines near-term science fiction with reporting to cover the intersection of technology, economics, and morality. He is also an instigator who has worked in the realms of technology policy, interaction design, climate risk, artificial intelligence, and disaster response. Brett regularly consults with corporations, universities, political campaigns, and governments.

In 2007, Brett launched America's first online voter registration platform, Your Revolution, which allowed voters in Washington state and Arizona to register to vote instantly from their Facebook profiles. In 2008, Brett directed Online Organizing and Social Media for T. Boone Pickens' “Pickens Plan” campaign. He helped the campaign sign up over 1 million members in four months, and by the end of his involvement was responsible for managing a community of 1.8 million members, who in turn sent more than 8 million letters to Congress. Then-Seattle mayor Mike McGinn asked Brett to head his Government 2.0 Task Force to create strategies for innovating government and the civic process. The task force helped launch Seattle's Code for America project. 

Brett has also worked with the International Centre for Earth Simulation based in Geneva, Switzerland, working directly with founder Bob Bishop to evaluate pilot projects deploying supercomputing centers to conduct climate risk modeling. Brett is also a co-founder of Lumana Credit, a micro-finance cooperative based in Ghana.