Love the site, thought I would try to contribute.
What works for me is one of those Reach Easy back things, the kind that you plug into the wall.
I was having trouble with my arms getting tired all the time. I bought a massager because I wanted to increase the blood flow in my arms so they would not tire so often.I used it on my arms, then started jerking off. One thing led to another my arms got tired, thats when I decided to see if the reach easy would work. the first couple of times nothing happened. Then the third day I was about to give up, and it became intense. I SCREAMED AND CARRIED ON LIKE SOME GIRL WHEN I FINALLY CAME. It was the most awesome feelings, I came in four big puddles the first one hitting my forehead. Now whenever I use a massager I always close my eyes when I cum.