If you are a bit of an adrenaline junkie this is for you. As far as your lawyer is concerned, though, I didn't tell you this stuff.

1. Stand at the very edge of high places.
As long as the wind is in your face and not at your back, this is epic. If you have a small, low bridge that you're fairly comfortable with, stand on the railing of that too.

2. Get out on an open freeway and just drive fast.
Know what speeds are acceptable on that particular road before you try this. When you do need to slow down, be ready for it and don't grind on the brakes. I recommend doing this one when coming down an empty overpass.
For extra adrenaline: A lot of local raceways have open times where you can pay to just get on the track and floor it.

3. Tell off a jerk.
Especially if everyone else just puts up with him and you know they shouldn't. It's so much fun to watch the jerk turn red and just awkwardly say "okay." Btw, this doesn't work very well with insults; only do this when you know you are right and can make a logical, emotionally checked statement that will hit home in the setting. Also, be sure that you talk to him pretty quickly after an incident. Don't confront anyone over something they won't remember right away.

4. Go out of your way to be nice to people.
The only reason I call this dangerous is because sometimes you'll come in contact with some shady characters, and sometimes people will be ungrateful and get you down. You have to carry yourself with presence and confidence.  That being said, nothing is more gratifying than making someone else smile. Give some money to that homeless guy. Just use discretion and give to people who seem consistent and sincere. Better yet, give food! A lot of sincere homeless folks will stand near a fast-food place. Go buy them something. You'll be smiling for a while after.

5. Pull over on the side of the interstate and just stand at your tailgate.
The feeling of constant heavy wind and the sound of trucks screaming by at 80 MPH is ridiculously epic. The sheer power that each of those vehicles have behind them, and you standing so close? Love it. DO NOT STAND BETWEEN YOUR OWN CAR AND THE ROAD. Stay back at least eight or ten feet from the yellow line. I don't recommend trying this very often, since pulling over for anything other than an emergency is a bit dangerous in the first place, but give it a shot if you're already in a roadside situation.

6. Jump over everything instead of going around it.
Especially if you're running. Try not to have to slow down. This one's easy because there are a lot of places with things to jump over, and it's really not that dangerous. The worst thing that's happened to me when trying this was a sprained ankle, and that's because I jumped into a bush.

Don't ask.

7. Get lost.
Literally, get so lost that you have no idea how to get home. Turn down whatever road appeals to you. Drive until you're tired of driving. Enjoy all the scenery, and don't stress about not knowing where you are. When you're ready to go back, just turn on your GPS.

And there you have it! As a disclaimer, don't be reckless with any adrenaline-charged activities. It takes the fun out of it when you realize that other people might be nervous because of your actions. Use common sense, and have fun!