I've been finding way too many people out there who don't think that they're creative.
Creativity is just the practical application of our imagination. We all have an imagination and, at some point in our lives, we have all been creative. It's just really easy to fall out of practice and merge with the null.
Here's an activity for you. Go buy a small box of crayons and a pad of paper. Think of something that is accepted practice but you would like to change (i.e. your office's use of power point, “tps reports,” logic models). Now try to sketch out the problem, the solution, or the sticking point with your crayons.
Tip: use as many pieces of paper as you want and don't worry about the quality of the artwork.
If you're planning to do this, let me know in the comments. I would also love to see what you came up with.