You can get your scuba licenses and go on some crazy dives for $500 total, or less.
Learn to snowboard? $500, again, give or take.
Fly an airplane? Look it up. It ain't so much.
International travel? Trivially easy and inexpensive in the days of Skype, Matrix ITA flight search + kayak.com, Wikitravel, and Google.
That list of stuff you're "going to get to someday"?
You're not going to get to it. You could do half the stuff on the list by the end of next year if you were serious.
Sorry if I'm interrupting American Idol here. Your dreams? You could just do them. Stop lying to yourself and saying you're going to do them, because you're not - unless you start right now.