Nedarim 56 - A bed for good fortune
If one vows not to enter a house, he can still use the attic - so says Rabbi Meir, because people think of attic as something separate from the house. But the Sages disagree, since they estimate that people mean all of the house, including the attic. However, if he specifically said that he won't enter the attic, all agree that he meant that, and he can still enter the house.
If one vowed not to sleep in a bed , he is still allowed to use a special bed called "dargash," - which is again the opinion of Rabbi Meir. But what is dargash?
Ulla said that this is a bed of good fortune. It was customary to designate a bed specifically for a good angel protecting the home, as a way of eliciting good fortune for the house. Since this "dargash" is mentioned in many other rules, the Talmud argues that it could not be the good fortune bed, and that dargash means a bed with leather interior and with loops in which the ropes were tied, and could be untied. So the bed of good fortune is not disproved, but it must go under a different name.
Art: The Bedroom By Pieter De Hooch