BOB

With the winter storms that hit here in Texas, made me realize I really should start carrying a BOB. My wife actually agreed that it was a good idea. I had a backpack that I stuffed a couple blankets in, and some socks and sweater for each of us. Put a couple of Quaker oats chewy bars in there too. So now that things have settled a little bit, I'd actually like to setup a couple permanent ones for the car and maybe one large one to keep at home. So what is a good size/style/type of bag to use as a BOB. And also some good ideas of things to keep in these bags.