A lecture about English
A linguistics professor was lecturing to his English class one day. "In English," he said, "A double negative forms a positive. In some languages, though, such as Russian, a double negative is still a negative. However, there is no language wherein a double positive can form a negative."

A voice from the back of the room piped up, "Yeah, right."

All Male Jury
A lawyer addresses an all male jury: "Gentlemen, shall we cast this beautiful, lonely young lady into a dim cell in a prison, or shall we return her to her oceanside beach condo, Ocean City, telephone Number 555-4531?"