I must be doing something wrong, because I just get orgasms from having lots of sex several times of day.
I feel so deprived. 
This happens to me, too. It’s not orgasmic, but when I have a sore back and take some painkillers, when it kicks in, I feel sooooo relaxed.
My favorite orgasmic moment is stepping into a hot shower. When that hot water runs down your body, it just feels so good. I love hot showers!
And even better than that, my favorite grocery store makes chocolate-espresso cheesecake, with a chocolate-covered coffee bean on top, and lots of chocolate shavings. Instant happiness! The only food I’ve ever had that’s more orgasmic than that is Bittersweet Chocolate Mousse Cake (from Cook’s Illustrated). Mmmmmm, that’s good stuff!
ME
In the food category, Belgian waffles with plenty of syrup and real butter and a big glass of ice cold milk. What a rush!
In music, when I was in freshman chorus we learned a piece, I can’t remember what it was now, perhaps something by Mozart, and there was a part where we held a long note. We worked on it without the piano accompaniment, and the first time we sang it with the piano and heard the harmony it was doing under our long note, my hair stood on end, it was so beautiful and unexpected.
And the day I sat down at the piano and figured out a bit of the Rhapsody in Blue, and it turned out to be easier than I expected. Not quite at the level of the first two, but I was pretty damn pleased with myself that day.
My current hobby is driving my sports car on race tracks (not racing, just driving fast). It’s gratifying to be taking a corner as fast as you can, and catching a slide before you go out of control. It’s exhilarating, but I can’t say I’d call any of my driving experiences really orgasmic. At least not yet.
If I saw Bjork or Emiliana Torrini in concert, I would probably literally faint. “Birthday”, along with nearly every Torrini song, makes me feel that way.
What does ‘orgasmic’ mean? 
Strawberry Pocky and pear Jelly Bellies. Particularly the first in a pack.
Good classical music.
Sliding in between freshly-laundered sheets on a friday night, knowing you have the whole weekend ahead of you.
Waking up at midnight on a Sunday or Saturday morning, and then just rolling over and going back to sleep…
Entering a reeeeaalllly big library/bookstore. I have been known to moan and go weak at the knees with this.
Getting a book I’ve been expecting for ages that completes/continues a series I love.
A good back scratching…
When I get poison ivy, and I run /really/ hot water on it, it’s mind-numbingly, excruciantingly, eyes-rolling-up-in-my-head, using the Lord’s name in vain, awesome. I have to hold on to things so I don’t fall down. It’s kinda like what Incubus was talking about, but I don’t think it’s worth getting poison ivy on purpose just to experience it.
It also seems to eliminate the itching for several hours.