Dining
A consensus "up" has to be decided if you want to all dine facing the same rotational orientation: that is, if all the diners want to look "rightside-up" while they dine with each other. Maybe some scum like to fuck with newcomers by eating/conversing upside-down?
Space bedroom, with video by Canadian astronaut Chris Hadfield
Space toilet.
The toilet has "stirrups" so that you are not propelled off the toilet by the force of your exiting turd. I am not joking. The handles also help you stay on-target and on-toilet. The toilet has a vacuum force behind it.