A customer sent an order to a distributor...
A customer sent an order to a distributor for a large amount of goods totaling a great deal of money. The distributor noticed that the previous bill hadn't been paid. The collections manager left a voicemail for them saying, "We can't ship your new order until you pay for the last one."The next day the collections manager received a collect phone call,"Please cancel the order. We can't wait that long."

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."