I've become a day writer: most people start as night writers, and I used to be, but something happened to my endocrine system. I do miss the 3 A.M. writing jags.
I miss my pre-Internet brain, but that doesn't help anything. We can only go forward.
I miss the silliness of the Nineties. What would society be like if 9/11 never happened? If that silliness was extended forever?
I miss the reference section at the library. I used to go there twice a week on missions. Now everywhere's a research library and I can't get an elitist kick from it any more.