What are some alternatives?
When comparing Stormboard and A Web Whiteboard, you can also consider the following products
MindMeister - Create, share and collaboratively work on mind maps with MindMeister, the leading online mind mapping software. Includes apps for iPhone, iPad and Android.
RealtimeBoard - RealtimeBoard is an online collaboration software created as a team collaboration and online brainstorming tool. It's super easy to use & free!
XMind - XMind is a brainstorming and mind mapping application.
Aggie.io - Draw a picture together with your friends in real-time over the internet in your browser.
MindManager - With MindManager, flexible mind maps promote freeform thinking and quick organization of ideas, so creativity and productivity can live in harmony.
DrawPile - Drawpile is a drawing program that lets you share the canvas with other users in real time.