I dismissed this at first, I even made the thread as a "I dont need to take this seriously right? heh heh..." sort of thing, but after forbidding myself to daydream for an afternoon I was so damned productive compared to before that I had to admit it was a drain on my life, if only I could become a writer I would never run out of material, no seriously, have like 20 sketched out custom fantasy worlds and about 3 fully fleshed out ones with multiple cultures, politics, religions, and history and even differing physics which I have ironed out to have internal consistency, like how a universe containing 3 different layered sub-universes all with vastly different (and worked out) sets of physical laws that interact in real time would actually work, I have material for dozens of books, but I suck at narrative, so all I get is a vacant expression on my face sometimes when I visit them.
Still, no matter how fleshed out your daydream life is, 90% is a but much isnt it?