The rest of the book case, I'll fill after getting the assignment.

No assignment whatsoever. This is just for fun :). The only requirements I suggest (feel free to break them) is that it has to do with computer programming. Obviously there is a fair amount of grey area (math, sciences, data formats), feel free to suggest whatever comes to mind. Say you had a month (or a year) to write whatever type of code you wanted. What would it be and what kinds of documentation would you need?