There is a planned mass march on Parliament on the 5th of November 2015, with people meeting up at 6pm in Trafalgar Square then marching down Whitehall to Parliament at 6:30pm. A Facebook event has been set up for this; https://www.facebook.com/events/485894658146587/
You can view a video of last years event here: https://www.youtube.com/watch?v=2QyvhLzGq98