Do the Audio gods shine upon you?

Has anyone else had this experience or am I just nuts? You sit down for a quiet evening of Hi Fi listening and after some warmup time you suddenly realize that your system sounds dramatically better than it did the night before. I am talking about those little things like more resolution, low level detail. You know, those things that turn audiophiles on. I am almost afraid to turn my system on again for fear that the "audio gods" have abandoned me.