When I get my own place, like my OWN place...I will have a disco ball(s).
Why? Because they are awesome, because they are pretty, and because there are so many ways to decorate with them. When people come over, they will say "wow, you have a disco ball in your kitchen/bedroom/living room?" and I will proudly show them off.
And for the holidays, disco balls are beautiful in wreaths and other arrangements