C#, I learned C# because it is a widely used language in the work field.
C++, I have grown fond of this beginner friendly language due to it's speed.
Python, I have experimented with python and find it very useful with all of its built in feartures and powerful functions.
Android, I have made a couple of side project Android applications for the sake of learning both Java and the Android OS. It is one of the best ways to learn and improve in programming