The Brazilian side of Iguazu Falls is easily accessible from the Argentinian side. However, make sure you have a Brazilian Visa - if applicable.
Besides the helicopter ride over the falls (Brazilian airspace only) and the Tropical Bird Park, the Brazilian side offers terrific views of the Argentinian side of the falls, and up the throat of the Devil's Throat! In addition, the falls on the Brazilian side - while fewer - equal the Argentine side in splendor.
The fine art landscape photography of Iguazu Falls from Margie and Bill Murr is almost as spectacular as being there.