Amid extremely tight security, demonstrators have been prevented from getting close to the G20 summit in East London. But some people did venture to the site, perhaps hoping leaders would get a passing glimpse of their demands while being driven to the ExCel Centre.Protests were also low-key, and good-natured, around the London Stock Exchange. Despite fears of a plan to disrupt the markets, police had to contend with nothing more menacing than a giant game of Monopoly. Decrying people making reckless decisions with money, a small group of activists made their point. As the talks began there was something of a carnival atmosphere to the protests. But, after yesterday’s clashes, authorities are bracing themselves for further violence.