I don't know what exactly you feel, but I get a kind of "rush," I suppose, from going out to the middle of a field on a clear night, laying down, and just staring at the stars and thinking about what's going on out there. There's a certain feeling about it that is probably comparable to what you feel during a "faith experience." For me, just knowing that I'm here, that I'm in this universe, on this planet, living this life, is enough.
I had the opportunity to listen to a talk given by former evangelical preacher Dan Barker. One of the interesting things that he said was that when he was a Christian, he could feel something inside of him, a kind of "high," when he would speak in tongues or get really into a sermon he was doing. He gets the same feeling nowadays while playing jazz piano.