I woke up at 7am one morning in January, when I was home for break, to the sound of my car starting up--Cold start + LTs + cut-out = distinct sound in my neighborhood--I ran out to the livingroom window & saw my dad driving off with my car.
I considered hiding the keys after that, but he's topped the tank off every time so far so no complaints on my end
I let two of my roommates drive it--they didn't get on it, just for a mile or so around campus, but they didn't like it.
When my younger brother was really timid about driving I took him out to 287, past 208 but before 17...the place with the long open stretches of highway, and let him open it up a little bit. Giving the keys to this car to a 17 year old isn't the smartest thing, but the point was to show him that he needs to keep his eyes on the road & everything around him, rather than glued to the speedo. It worked; I'm no longer afraid to drive with him