Program Ideas

I finished learning about pointers and pointers to arrays and wrote an overly complicated Fibonacci Buttsorter, then realised i needed to know nothing about pointers and pointers to arrays and wrote a quick hack version that took 1/4 of the lines and 1/10 of the time. Anyway, doing that I learned alot of new. important stuff about programming. So, [spoiler]/prog/[spoiler] any ideas of quick programs like this I can make that will teach me interesting/important stuff about programming? And yes, I have read SICP

And yes, I have read SICP
I finished learning about pointers and pointers to arrays