A friend frequently asks me for help with Java homework.
Today we spent half an hour figuring out how to use some ass-backwards linked list implementation his lecturer provided.
The list itself acted like an iterator, keeping track of a 'current' element that had to be reset to the list's head manually every time you want to iterate over the list. There were insert and append methods that call each other for no good reason and most methods would throw the same generic checked exception.
Also they're told to use BlueJ which has the ugliest debugging tools i've ever seen.