Intelligo's Interact Pane has a live polling feature.
The organiser will set a multiple-choice poll to 'go live' at a certain point during the event. It will appear in the audience's Interact Pane instantly, and everyone in the audience is able to cast one multiple-choice vote.
When the audince has cast their votes, polling is closed, and the results can be shown to the audience. Alternatively, a closed poll does not show the results to the audience.
There can be an unlimited number of polls during a session.