I want to be able to learn something new. I have no idea what to do, but I am willing to try almost anything. I really want to do this for no particular reason at all. It can be educational, fun, or even beneficial. Currently I am learning to write with my left hand and I am also trying to meditate everyday for 20 minutes.
Using and making a sling (not a slingshot), it is really a lot of fun and a activity for outside :D just go far away from anything with value onto a field or in a forest, your first throws will go anywhere. This is the best guide on making/throwing I could find http://slinging.org/index.php?page=how-to-build-and-use-a-traditional-apache-sling—l-w-forsyth
You can try Jiu jitsu and MMA, thats an amazing way of meditation for me and I enjoy it so much:)
Or you can try physics as some people already said. I am reading some amazing books about relativity and quantum mechanics. Its so interesting.
Read a lot of books!
I just wanted to thank everyone for all their great ideas. I think I will try all of them a few times and see what I enjoy the most. Then I will go from there. I also want to play a few instruments (Violin, Ukulele, Guitar, and maybe something else) Any tips and ideas on where to get these will be greatly appreciated. I would also like if anyone has an idea on what the fourth instrument should be, Thank you. :)
Might you have any interest in learning harmonica? You can buy one for about $7 at guitar center, it’s portable, it’s simple to learn. I’d consider that a great starter instrument. I learned how to play just from watching youtube and messing around.