Picketing the RNC. It's sort of counterintuitive, but anti-abortion protesters cannot picket the Republican National Convention. Two such protesters who picketed at the 2004 Republican National Convention were arrested for not moving themselves to an area reserved for picketing when instructed to do so by the police. The protesters brought an action under 42 U.S.C. 1983, claiming that the police had violated their First and Fourth Amendment rights. The District Court granted summary judgment to the Police, and the Second Circuit affirmed, claiming that what was involved was a valid time, place and manner restriction.
The decision in Marcavage v. City of New York can be found here.