This one got me thinking, so I figured I would throw this out there.
My big experience happened when I was 25. I had been chasing the Enlightenment thing pretty hard via Alan Watts and other Zen cats. I was still in school studying Philosophy so I basically had all day to rip ideas apart searching for the basic Truth.
One day, my girlfriend blew me off for a date that I was planning and I was totally convinced that she was cheating on me. I drove back to my apartment and ended up lying on the bathroom floor crying so hard that a pool of snot and tears formed under my head. I wasn't so much suicidal as suicide was a forgone conclusion, it was just when it would happen that was in question. I just cried until I had nothing left and passed out.
Anyways, I woke up the next day with absolutely no energy and grabbed my headphones and laid down on the floor. What happened next is really hard to describe, but for the first time I completely gave up on everything and was just me. At first I was pure rage, then I cried alot. Then I thought of how much I loved my little sister and these waves of Love started building in me. It became quite overwhelming at one point.
Then my attention was drawn to different points in my body and I started feeling these knots start to untie themselves (best way of describing it: I just allowed my attention to flow to various points in my body and sooner or later something would release). I then put my attention on the feeling of "I" and tried to find it...and I couldn't. That realization was like getting hit with a wrecking ball. I didn't know what I was.
That discovery blew the door off the experience. I then started spontaneously understanding or "knowing things": how the ego was fictional, how the mind was purely a tool and always partially wrong, that everyone was chasing love no matter what they were doing, that I was not a human but consciousness, that it was impossible to die. I knew that I was now awake in a way I had never been before and was shocked that it was so simple and that everyone was missing it.
It was at this point that a --and this is the only way I can describe it-- a whirlpool opened up in the middle of my abdomen and sucked me inside out through myself it to Pure, Peaceful, Emptiness...which was me. I expanded backwards until the experience of the earth was just a speck of dust. I was just the emptiness/consciousness that is I am.
Then I came back to my body, my story, etc. I then spent the next 3 years building an obnoxious dip-s-h-i-t of a character as the "Mystic" who had achieved Enlightenment in the past and was only waiting for the full event. I grew long hair and wore beads. And I chased that experience like heroin. Drugs were the closest that I got, but they were unreliable and hard to come by.
To this day I have no idea what happened. Was it a mystical experience? was it a seeing of Truth?
But I still chase that experience everyday.