TitanPad could be used as a platform for quickly hosting and recording an online brainstorming session with your students. As accounts aren't necessary you won't lose any classroom time to getting students through a registration process.
Real-time collaboration and chat.
Use Webspiration to map out ideas, organize with outlines and collaborate online with teams or colleagues. Webspiration unleashes your creativity, strengthens organizational skills, and transforms your ideas and information into knowledge.