Brazilian side of Iguazu Falls
Today I took a day trip over to Brazil. They also have an Iguazu Falls National Park (or Iguacu, as they spell it in Brazil), but it's really more for looking at the Argentine side of the falls.
Advice to those who might come to Iguazu Falls:
1. The Brazilian side really only takes a couple hours to see. 3-3.5 hours max if you also have lunch here. There's only one "hiking" trail (it's paved) that's included in your ticket, and it's to look at the other side. The park is also close to the airport on the Brazilian side, so you could fit it in before an afternoon flight.
2. People suggest making sure you see it when it's sunny - I think this is so you can see the rainbows.
3. People also suggest seeing the Brazilian side first, then the Argetine side, but I really don't think it makes a difference. You'll be able to recognize all of the places you've been, if you see the Brazilian side second.