*Petra (Jordan; my photos at left)
*Brazil's statue of Christ the Redeemer (on top of the Corcovado mountain in Rio de Janeiro)
*Macchu Picchu (Peru)
*Chichen Itza (Mexico)
*The Roman Colosseum
*Taj Mahal (India)
*The Great Wall of China
In addition, "The pyramids of Giza, the only surviving structures from the original seven wonders of the ancient world, were assured of retaining their status in addition to the new seven after indignant Egyptian officials said it was a disgrace they had to compete."
I've visited six of these (haven't been to the Great Wall or Taj Mahal, unfortunately), and I think they're all excellent choices. I'd add a few more I've visited that I think are amazing (in no particular order):
*Tikal (Guatemala)
*Cuzco/Sacred Valley of the Incas (Peru)
*Eiffel Tower (Paris)
*Temple Mount/Dome of the Rock (Jerusalem)
*Abu Simbel (Egypt)
*Aswan Dam (Egypt)
*Luxor (Egypt)
*Alhambra (Granada, Spain)
*Jerash (Jordan)
*Statue of Liberty (New York)
*Empire State Building (New York)
Of course, there are many others; friends tell me that Angkor Wat (Cambodia) and the Haghia Sophia (Istanbul), to take just two, are amazing. How about you; what are the most "wondrous" man-made structures you've ever seen? What do you WANT to see before you die?
(more photos - Tikal, Temple Mount, Macchu Picchu) after the flip)