Comment threads of news items can be pretty much echo chambers but every once in a while, some posts a random comment that leads to a rich variety of punny responses.
Comment Threads of Interest
I lurk on various news and special interest forums. Occasionally the commenters get carried away with cascading puns:
Heisenberg is driving down a road when a cop stops him. The cop comes up to the window and says, “Do you know how fast you were going?” Heisenberg responds, “No, but I know where I am.”