What was your first (useful) program?

I am learning programming right now, and so far I didn't succeed in creating a powerful virus in C or an enterprise GUI in C++, but I did code lolcocks_folder.py
What was your first useful program? (Not helloworld.c or another example from K&R)

A BASIC program that would find the factors of 121.  For bonus points on a homework assignment.  In third grade.