Let's start off with something lighter.
Write a parody piece. Usually this can be done for an existing song, poem, or other work. Writing parodies is not only fun, but it allows you to examine an existing structure and work within/around it. One of the biggest names in parody is Weird Al, so give him a listen if you've somehow managed to live your life without doing so.
Parodies can be about anything you want regardless of original content, so have fun!