I've done it. What, specifically, would you like to know about the experience?
It was, without doubt, the most thrilling, exciting, adrenaline pumped activity I've ever done. It takes all day. You begin a training course in the morning. First it's theoretical, watching videos and seeing photos of "good" chutes vs. "bad" chutes (this bit's scary as all hell). After lunch, you go into a hangar and get into a real harness that's suspended from the ceiling, just so you know what it feels like in the air.
At the end of all that, and after you sign a waiver (yikes!) you put on a jumpsuit, parachute and helmet, get into a gutted Cessna with five other people (three jumpers, a jump master, and the pilot) and take off. When it's your turn, you step out onto the wing of the plane, hanging on with one hand on the doorframe, the other on a strut, and then you just...let go.
The jumpmaster throws the "pilot chute" out after you, and that pulls the ripcord automatically (no freefalling). You count to ten and check your chute because, if you'll recall, you know what a "good" chute looks like. If you're chute is "good" you will live, and you shout and whoop into the wild blue yonder until you touch safely to the earth.
Any more questions, feel free to ask here, or PM me.