an example of no pun intended from wiki answers
"A manager at a company is very heavy. One day he comes in with an auditor who is evaluating how the manager runs his department. The manager sees a number of things that are unacceptable, and he starts dressing down his workers in harsh tones. "I've told you guys that we do this and we do that and we do the other, and you still don't get it. Please follow my instructions and get those things done in the way I've aske you to do them!"
The auditor looks at the manager and says, "I've got to hand it to you, and, no pun intended, you really know how to throw your weight around."
The word "weight" here refers to the manager's authority in his department, and not to the extra pounds he carries. [This is offered to make the point. It would be in bad taste to say something like that to someone who is overweight.]
No pun intended means they did not mean for what they said to be a pun."
It is better to keep your mouth closed and let people think you are a fool than to open it and remove all doubt...
-Mark Twain