One of the first exercises for Skillsup students is painting material cubes. I still enjoy it even after fiishing the course. There is a great temptation to skip right to props creation or at least to complicated materials but I remind myself that I've been studying for 11 years before going to university. I enjoy the concepting part of the work. Even though I abandon several ideas it's fun to do. The main difficulty for me is working with chiaroscuro. It stresses the need for learning construction drawing. My favouite part is polishing and adding glow. It's like meditation. Now I'm working on the lava cube, it's the best for feeling flow!
I know something about creative search... :)