Here's one that I just did for myself. I had painted a really pretty abstract background with acrylic paints quite a while ago. Today I sat down to sketch out some ideas trying to figure out what to do with it.
Once I had an idea, I dropped it into the computer and got to work experimenting with the different layers. I have had several miscellaneous things going on this week, things unrelated to art, and was feeling pretty unproductive. Now I feel better.