When you're stuck on a problem, or not even stuck but you just want to boost your creative/out-of-the-box thinking...
Take a shower. When I'm thinking about a problem and I take a shower, the ideas and thoughts just start popping up, one after each other, or sometimes even two at the same time. It's amazing. And it works every time.
Sometimes the amount of thoughts and ideas is so much that I need a piece of paper to write everything down immediately when I come out, otherwise I'll forget stuff before I leave the bathrooom.
If you work from home, it can be beneficial to not shower in the morning (because then the mind is fresh enough to be creative), but rather doing it somewhere before noon or in the afternoon. (of course this depends on what you're working on)