Knee Shaking Orgasms!

How many of you have had a knee shaking insane orgasm to where you almost passed out or had you seeing stars?

I've had a few and keep trying for them. My first time I was fingering myself and intensely rubbing my g-spot and had to sit down cause I thought i was going to pass out.
Another time, I had Rambone up my ass and it was good, i was in the shower and decided to try and give myself and enema at the same time. So i had an ass full of fluid and a huge cock deep inside me, and I collapsed! shooting the cock and fluid out of my ass and stars were all over my vision and I shook for 10 mins before i could move.
Again this morning, I was fucking myself last night and it was fun. But this morning i got out my collossus dong and put it all the way inside my sore hole, and you may know what im talking about, but the next morning you are so wet! I quickly was bouncing up and down balls deep until i finally fell forward laying on my stomach, ass up, gaped wide open, and i was cumming hard! That orgasm was so intense!

Anyone else have this? how do you achieve it?