Some of the arranged music I've practiced heavily at one point or another:
In my second year of high school, my grandfather decided to be extremely generous, and bought me a Yamaha Clavinova CLP-124, because he was happy that I was playing the piano so much, and wanted to encourage me to continue. Ten years later, I'm still playing it and treasuring it, particularly because he gave it to me shortly before he passed away.
During college, I gradually played less sheet music and experimented more with improvisation, and eventually became decent at improvising through-composed (structureless) music. Currently, I'm working on fake book material, in an attempt to introduce more structure into my improvisation.