I have to say that there are some ways of having sex that, for me at least, are, or have been, truly mind blowing. Anal sex comes to mind. Various other variations that I might someday divulge also spring to mind. The head of my Johnson tends to get quite sensitivie so sometimes being on the receiving end of oral sex can be a bit ... well, sensitive.
Masturbation can be pretty great when done well too. With masturbation, you can control more variables than with sex with another (person).
Now, I must say that the one time I was involved in a threesome was absolutely fantastic
, but that is more a comment on the entire experience than on the orgasms themselves.