Code.gov - Share & reuse open source code from the Federal Government
Simple Poll - The easiest way to create polls in Slack
CodeShare.io - Realtime code sharing for developers
Curious Polls - Answer a question once a day for the chance to win £100/$100
Twitter Polls - Polls embedded in tweets
Urbanpinion - Citizens engagement platform that lets you create a landing page with an interactive map in just a few steps, launch a survey and collect citizens' ideas and votes - and make the right decisions for the city development.