The simplest of things I started never made it till the end.
Publish a book.
Pain Graffiti on a public wall (probably not allowed in most places, will find one!)
Go on a Road Trip across Malaysian Peninsula
Attend Ha'erbin Ice Festival
Attend Germany Oktoberfest
Celebrate Diwali in Nepal
Celebrate Holi in India
Be at Times Square, New York for one Christmas
Hold a street photography exhibit (at some point, when my skills are polished enough)
Swim with Sharks
Trek the Inca Trail to Machu Pichu
Get in and (of course) out of Prison.
Visit Northern Iraq
Witness the migration at Serengeti, Tanzania