Write your own programs to solve your own problems! They can either be real problems, or just stuff you're interested in. Over the last few years I've written a

Write your own programs to solve your own problems! They can either be real problems, or just stuff you're interested in. Over the last few years I've written a program to help me cheat at Scrabble (great for creatively thinking around a problem, especially trying to optimize it), and wrote a very basic 2D game engine, just to see how it was done. Sometimes my SO complains about something and I write a little app to solve that problem.