Some of the best feelings I've ever had were in high school during basketball season.
I was never really a sport guy in the varsity sense, and I had tried out for basketball in 11th grade after I recovered from my broken ankle. I didn't make the team.
I continued to work out and practice with the team. Over the summer, I went to practice almost every day, worked out, ran hard for 3 hours. Finally, the asst coaches (who worked with us over the summer) told me during the summer that despite tryouts in the fall, I was making the team. I started to work even harder.
Here comes great feeling #1: During an early practice in the fall, we were doing ball handling drills and doing a move to the basket. After doing it a few times and getting my finger rolls very high above the rim, I decided, on a whim, to try to dunk the ball. Now, at the time, I'm this skinny 6'2ish white guy (no offense), but I did a little in and out move, and flew above the rim for a thunderous one handed dunk. The whole practice stopped. The kid who couldn't make the team last year was elevating above the rim. I kept doing it
Now, fast forward to the regular season. My school was about 1500 kids, 9-12 grade. It was the last game of the season before the playoffs - senior recognition night. We were playing our arch rivals. During warmups, I just looked around. Nothing but people packing bleachers. Our kids going crazy, the other team's supporters yellin right back. Not an empty seat in the house. During the layup line, I start doing these insane 2 handed dunks, wowing the crowd. They cheered me for more.
Great feeling #2: adrenaline rush given to me by the crowd ^
Now, I didn't really play much in that game, or much in the season actually (the coach had a problem with using new people), but when we won that game and sent those f*ckers home.
Oh, and beating the #1 ranked team in the Nassau county semifinals helped too - the most noise I've ever heard out of our locker room in SUNY Westbury (where we played playoff games).
Nothin like sports for great feelings - nothing like knowing girls are watching you when you dunk :P