I can and do it a lot.
Have you ever heard the phrase "Let me sleep on it"?
If I have been having a difficult time figuring out a problem I will sleep on it.
With my mind free from distractions I am more capable of finding a good solution to the problem I have been working on.
Then there are those times where I change my dream and dream about what I wish. I used to do this a lot when I would catch myself dreaming about work. I hated doing that!
I would dream about fishing instead. Of course that made matters worse because then I wanted to go fishing for real when I awoke.