Imagine being able to watch the Sunrise at Mt.Fuji, then watching the sun break over the horizon at the Great Wall, then across over the Ganges, following its course to watch the sunrise over the Wagah border, maybe the Wailing Wall at Jerusalem, somewhere along the Seine, watch the sun slowly emerge across the Atlantic as one stood on the Brooklyn bridge, at the Grand Canyon, maybe at the Golden Gate bridge and at Hawaii, along its sandy beaches.
This is by no means an exhaustive list, the sort of places where one can watch the sunrise/sunset is just about infinite, but the very thought of wanting to do it all on the same day is already giving me goose-bumps. I hope someone can do it sometime.
Astronauts are able to see some splendid sights, apparently. Lucky guys, them.
One thing I must say, though, is that the sun or the sky or the horizon in general looks its best when you are with someone you love.
Edit:Something similar happened a few days ago with a 24 hour all-around-the-globe concert, for Live Earth. Wish I were there to witness each event in all those places one after another.