Stop me if you've heard this one...

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.”

A writer died and was given the option of going to heaven or hell. She decided to check out each place first. As the writer descended into the fiery pits, she saw row upon row of writers chained to their desks in a steaming sweatshop. As they worked, they were repeatedly whipped with thorny lashes.
“Oh my,” said the writer. “Let me see heaven now.”
A few moments later, as she ascended into heaven, she saw rows of writers, chained to their desks in a steaming sweatshop. As they worked, they, too, were whipped with thorny lashes.
“Wait a minute,” said the writer. “This is just as bad as hell!”
“Oh no, it’s not,” replied an unseen voice. “Here, your work gets published.”

A visitor to a certain college paused to admire the new Hemingway Hall that had been built on campus."It's a pleasure to see a building named for Ernest Hemingway," he said.

"Actually," said his guide, "it's named for Joshua Hemingway. No relation."

The visitor was astonished. "Was Joshua Hemingway a writer, also?"

"Yes, indeed," said his guide. "He wrote a check."

A screenwriter comes home to a burned down house. His sobbing and slightly-singed wife is standing outside. “What happened, honey?” the man asks.
“Oh, John, it was terrible,” she weeps. “I was cooking, the phone rang. It was your agent. Because I was on the phone, I didn’t notice the stove was on fire. It went up in second. Everything is gone. I nearly didn’t make it out of the house. Poor Fluffy is--”
“Wait, wait. Back up a minute,” The man says. “My agent called?”

Q. What's the difference between publishers and terrorists?

A. You can negotiate with terrorists.