Also used to describe the physical discomfort or displeasure felt after hearing a succession of lengthy jokes with dimwitted or inane punch lines.
Mental blue balls is often characterized by a dull headache or a distinct physical feeling of dismay, despondency, or dissatisfaction as the afflicted individual realizes he just wasted his valuable time and is "left hanging".
I got major mental blue balls today after two hours of brainstorming awesome ideas for killer iPhone apps, but no one had any idea how to implement them or even any project plans to get started.
You: whats the story guys?
Friend: oh no way man. theres no way we can tell the story its just too funny
You: NOW I HAVE MENTAL BLUE BALLS