This weekend developers and designers put their minds to coming up with the best ideas for new apps for sustainability, in the two day Cleanweb Hackathon held at NYU-ITP.

“Cleanweb Hackathon is a gathering to demonstrate the impact of applying information technology to resource constraints…Participants are tasked with building applications that tackle energy, waste, water, and other sustainability issues by leveraging web and mobile technologies. We challenge attendees on what they can do in 24 hours with utility, transport and smart grid datasets that might just change the world for the better.”

[top photo: Rachel Sterne]

Overall winner: Econofy, for green shopping match-ups of appliances and electronics, including an online calculator for comparing savings between models

Best energy app: NYCbldgs, “Find the best and worst performing building in New York”

Also noticed: 1v99.org, which lets users compare a jet set lifestyle to their own, in terms of energy usage (screengrab below):