Ask HN: Any great ideas about Open Source Mini Projects?

Hi folks, I wish to start a new open source project of my own as a mini project this semester. I wish to work more on the idea and extend it further in coming winter vacations. But the problem is - I'm running out of ideas, most of the ones that came to my mind have already been implemented! I would like to do something in Python (preferable), C,C++..can learn new lang if proj is interesting and have got 4 months with regular 8-6 course.

Please help out!