In the Artificial Neural Networks and Deep Learning course they gave us two project, or challenges, in which we had to develop a solution through neural networks to these two problems:
detecting if a plant was healthy or unhealthy based on pictures of its leaves;
developing a tool for time series forecasting on time series of various lengths and characteristics.
Personally, I didn't and don't really enjoy the approach of neural networks; I prefer more theoretical and statistical based methods as the ones employed in the other projects, rather than just create a network with no real method for defining its structure and parameters, then letting it learn and tuning it "hoping for the best". Nonetheless, it has been an interesting project.