Name for me your Top 5 Must-See-Before-You-Die destinations

[teddyFBI]

Poker has been very good to me this past year and I'm spoiling myself with a trip around the world next summer. I'd like to elicit from you all suggestions on places to hit.

What I've seen: really not much of anything -- basically I just did the 5 weeks of Western Europe thing after I graduated from College.

What I want from you: I don't want the typical general vacation destinations; i.e. 'you've got to go to Australia, Hawaii, Thailand, etc., etc.'. I can go to Barnes+Noble and poke through the "Let's Go" section to find good travel-friendly countries. What I'm looking for is completely unique / once-in-a-lifetime traveling ideas that you think I should hit in my 6 months I'm devoting to nothing but world travel. I want some of the world's truly amazing wonders that 5 years from now, I can look back on and think -- wow, it's damn cool I was able to do that / see that at the age of 26 before I had to settle down and get a real job. Unique doesn't mean it can't be touristy...I just mean a little more specific than "oh, go to XYZ country, it's a blast." Just some examples I've already got from friends of mine that have got my juices flowing:
a) Dive the Great Barrier Reef in Australia
b) Stay at the Ice Hotel in Sweden / Arctic Circle (I'm freakin stoked about this one)
c) safari somewhere in Africa
d) Climb Machu Pichu (sp?) in Peru
e) run with the bulls in Spain
f) Carnival in Brazil

Assume that money is not a limiting factor here.