I dreamt about a future version of the Justice League, made up of the children and proteges of the "modern" League. It took place in 2030 or thereabouts and was very science-fiction, though the action was a lot of the usual stuff-- secret villains in strange lairs, giant robot-monsters rampaging destruction. However, it was just entertaining enough, I thought, and then I realized I wasn't reading it, I was dreaming it, I was making it up as I went along.
Then I thought, hm, maybe I should actually pitch this to DC. I like the way it's shaping up.
So then I dropped back fully into non-lucid dream state and dreamt that, in fact, I wrote a limited series about this 2030-era League, and I was almost done writing the last issue when the first issue came out... but I was horrified to see that it had been entirely rewritten in editorial. Not just dialog and the like-- I mean, characters had been redefined, relationships had been changed, and the whole story had been moved back into the present day instead of the future.
Every time I think about getting back in and doing a bunch of mainstream writing, messages like this bubble up from my sub-conscious...