I don't, and haven't since I have been married.
There was a point at which I was glued to a scale, so I don't have one near me now. This was particularly helpful during pregnancy. I only found out what I weighed by my Dr. visits.
Mostly, I can tell if I am gaining or losing weight by how things fit. It helps me focus more on my overall body than a particular number. I am SO into hitting numbers I want (too much so).
Sometimes I do weigh myself if I am somewhere where there is a scale, just to see how things stand . :)