I lived with my parents for a few years during the recession, ruining their house with my greeting cards and tornado-like workstation that ate their first floor.  

I worked in the dining room on my laptop.  Occasionally Mom would slide open the dining room door and say something.

MOM:  Falling asleep?

ME (entering invoices):  Why would you think I was falling asleep?

MOM:  Just a suggestion!  Use your time wisely.