Many times I've had dreams about SRB2 throughout the past 10 years, but one of them that has stuck to me was this one where a map was posted on the MB and it was incredibly designed with little intricate pieces and high attention to detail. When I had this dream 2.1 didn't have slopes yet, so this level was such a godly beast. It was this metallic factory with real-time shifting floors and walls with a open space near the end as Sonic progressed through the booming music of this drum n' bass remix of Old ERZ2's theme.
When I woke up I was so disappointed but it was so vivid. Nowadays my memory of it has been fading but the feeling of wonder of the pure technical skill of such a map is still very much there for me.
Another dream I had was somewhere in 2015 where it had someone make real-time cutscenes in the SRB2 engine with all sorts of camera pans, characters doing things, and motion blur. It was very interesting but I later got disappointed when I woke up.