I've done quite a few of them already: Skydive. Move to NYC. Visit Boston (ahem). Learn to knit.
There are also quite a few that I haven't done yet: Learn sign language. Write a novel.
BUT, there is one thing that I just started and it is my new favorite. It makes me happier than I ever thought something like this could.
I have bought and am now learning how to play the violin!!
I know I suck at it, I know I do, but it doesn't matter. I enrolled in a Beginner Violin Adult Education course in Brookline that lasts 8 weeks and I love it. There are 7 of us in this course and I love the group setting because I don't feel as pressured as I would in a 1 on 1 setting.
The majority of us have never played violin before and I love how eclectic our group is. One student is in his 70s, there are some who are probably 40ish, then there are others who are younger, but we all have this one thing in common: we all want to learn how to play and always have.
I have so much love for this I can't even express it!