Nothing is better than prostateorgasms. It is in fact a pretty strange feeling but at the same time very fulfilling. My method is to use a large dildo and push it in all the way from the top. If the dildo is inside the ass all the time its much harder to reach the orgasm.

It is the pushing at the hole that makes it. When the orgasm comes closer the anal start to contract and thats when you really need to push the dildo in by force. If you do it at the right spot the orgasm finally will be forced to start. If lucky it will first be an explosion of squirting with no orgasm.