It's so true about sex. It's not always the case, but sometimes it just happens, that you're in that state of overwhelming passion and desire that you erase the world around you and just focus on the moment, that you feel like the universe.
And yes, as a musician it also happens to me sometimes when I got into that absolute creative flow that I basically forgot about the time passing.
Then I'm lucky enough to enjoy both sex and making music even when I'm not necessarily in that blessed state. But I feel the difference, and yet I don't chase it as a must.