I would suggest trying to contribute to various open-source projects e.g. in machine learning ("deep learning" is all the buzz). You could pick up a tool like K

I would suggest trying to contribute to various open-source projects e.g. in machine learning ("deep learning" is all the buzz). You could pick up a tool like Keras and see if that piques your interest. Similarly, you could try other areas such as security and see if you can contribute to some of the OSS such as Snort or OSSEC. Personally I find trying to work on an OSS project the best way to "try-before-you-buy".