When you have nothing to shoot you can go to the nearest bus-stop and shoot running cars. Use different shutter-speed for different effects. To freeze motion but still have wheels moving - around 1/1500, to make a natural motion blur - 1/20 or less. It's easier to make running cars images in manual mode, because it gives you a chance to choose suitable aperture and ISO depending on light conditions. Automate may just refuse to work properly or it can all the time make similar images according to it's own choice. Don't worry if while shooting moving objects you produce a lot of rubbish, because rubbish in such case is a very normal part of work. In the end you get few pictures which can be uploaded without too much bother: all logos and numbers will disappear themselves. Here is an example:
This picture appeared on DT only yesterday, and today it already has a sale. So easy ;) Good luck.