My little sister loves to knit too. I tease her all the time. Sadly enough, I think her and my big sister are going to be the only two aerospace engineers that rival Martha Stewart.
My big hobby is scrapbooking, but I don't have as much time to do that as I used to. I do it in one big effort and spend like a week on it, and about 5 hours a day because that's just how I have to work. I'm silly, I know.