Having read about the site http://www.todaysmeet.com in a couple of blogs, I had a look and thought I would give it a go. I put the link up on the IWB and the students jumped straight in. I asked them to set decimal multiplication questions for each other, challenging someone else in the class to answer their question. This worked really well, and seemed to spark a really healthy competitive spirit. It also started good discussion as students questioned each other and the answers.
All in all, a good resource which is free to start, and allows you to set a time limit on the length of time the “room” is available.
Check it out here, at todaysmeet