Have you tried Wallwisher yet? Wallwisher is an online bulletin board where people can post ideas or comments about a subject.
I find the site very easy to create walls. Once the wall is created, the site gives you the link so you can send it or post it for others to access. As people post their ideas, a simple refresh lets them or you see what others are thinking.
I have done this a couple of times this year. I find it interesting the students who are willing to post their ideas here but would not typically participate in a class discussion of the same topic. My students were engaged, and this was a great springboard for our class discussion.
This would be great for meetings or for a time when you are introducing a new concept. People could post ideas or questions here for all to see in real time. The walls remain accessible to the creator from the Wallwisher site.
I hope you find this useful. Let me know of a great way you have or are going to use it!