Once, a young fresher was reading the rules, and was more than perplexed at the place where they state
"All undergraduates, if they are Anglicans, must be in chapel each Sunday at eight."
Wracking his brains, he began a small rumour that spread through the town on the weekdays that followed; he
was not an Anglican, nor Nonconformist; his faith and religion was mere Heliolatry.
Saturday evening, our hero retired with a smile on his face and his bin at his door,
only to wake to a thunderous hammering, made by the porter, next morning at four.
Ah, how a little lie, told with great frequency, gains repercussions that no-one expects!
"Dawn's almost here, sir, the Chaplain expects you; go down to Main Court and you'll pay your respects."
This is no longer the rule, but it used to be. "His bin at his door" = standard Cambridge signal that you don't want to be disturbed in the morning.